Adventure Map Mechanics: Tips and Tricks (2024)

This is a guide that I originally released on Steam. There have been some minor formatting alterations to accommodate this site, but it is otherwise essentially the same as the original. If you found this guide helpful, please consider visiting the original guide page and giving it a thumbs up: https://steamcommunity.com/sharedfiles/filedetails/?id=1352667743

Constructing the aesthetics of an adventure map is one thing, but designing the mechanisms that make it work 'under the hood' is something else entirely. This guide contains instructions (with pictures) for building a variety of mechanisms that can be used for a number of different functions on an adventure map, including single-use switches, pseudo event flags, equipment checks, auto-activating mechanisms, and more! Also includes some more general tips for adventure map making, such as how to control player progression and manipulate enemy spawn rate.

Introduction
When creating an adventure map, there are a number of major factors that come into play. One of them is aesthetics, both in terms of how the world is built, and its inherent properties. Another important step is balancing the difficulty of the map, and making the areas actually fun to traverse. On top of these, behind (and occasionally within) the scenes we have mechanisms. Having constructed an adventure map once myself, I had to learn a few tricks to make everything work.

While it is simple enough to rig a switch so that it opens a passage previously blocked by Active Stone Blocks, there are much more powerful, subtle, and clever uses for mechanisms on a map that can allow for complex puzzles, highly precise progression checks, and even pseudo cutscenes, among other things. Some of these examples are based on mechanisms from my adventure map, while others are theoretical exercises that I didn't have the opportunity to implement. Nonetheless, all of these mechanisms have been properly tested, and are shown in action in the supplemental video at the end of this guide. There are also some other techniques for map construction, such as equipment checks, ways to manipulate enemy spawns, and methods of altering the terrain mid-game. Bear in mind that the mechanisms shown in this guide have all of their 'under the hood' pieces near to the player, for visibility and demonstration purposes. On an actual adventure map, the components would generally be stored off-screen.

If there is anything mentioned in this guide that you require more information on, you can look on the Terraria Wiki.[terraria.wiki.gg] You can also find some general instructions on using logic gates here.

This guide makes reference to hoiks on a few occasions. As I am not personally a hoik expert, you can look at ZeroGravitas's original thread on the subject[forums.terraria.org] for more information.

If there is some specific thing you wish to find quickly within the guide, you can use the table of contents above, or your browser's search function (generally ctrl + F).

Tools of the Trade: Tools, Activators, and Target Mechanisms
Before delving into the mechanisms themselves, it is first worth introducing some of the major tools and materials used in their construction.

Wire Manipulators and Other Tools:
The Grand Design: This potent wire manipulator is at the top of the list for useful items when constructing mechanisms. If you're using TEdit to construct your map (and you probably are), then this won't see as much use, but it is still useful to make changes during in-game testing, as it is capable of laying out or removing any of the four colors of wire, as well as actuators, from a great distance.

Actuation Rod: Another item that isn't strictly needed due to TEdit, it too is quite useful during testing, for the ability to toggle actuated blocks on and off without the need of a wire-based signal.

Wire: Hopefully I don't need to explain this one. Wires are placed down in multiple colors, with wire paths of the same color intersecting, but those of different colors not interacting. Upon receiving an impulse, anything connected to the wire will receive a signal as well, toggling lights, opening/closing doors, activating traps, etc.

Junction Boxes: Wires directly in contact with a junction box will not overlap, even if they are of the same color, allowing mechanisms to be further compacted.

Activation Devices:
Switches/Levers and Detonators: These mechanisms are the most basic means of sending an impulse down a wire. By right-clicking a swtich or lever, any wires overlapping them will receive an impulse. Either one can be placed on a wall or background wall, though the lever cannot be placed directly on the floor (it can be placed on wood platforms). Their function is identical, aside from the lever being larger. Detonators are slightly different in that they cannot be placed on walls or backwalls, and in addition to clicking them, they are triggered if a player physically falls on top of one. Triggering a detonator with wire will not only not trigger it, but will inhibit it from being activated through other means until it receives another wire impulse. Lastly, detonators have a short cooldown on activation, unlike switches and levers.

Pressure Plates: These can be placed on the floor, and stepping on one will send an impulse through any wire that touches it. These appear naturally in environmental traps in-game, activating nearby dart traps, and dropping boulders through now inactive stone blocks from above. They come in multiple colors, including a Lihzahrd variant. The gray, brown, blue, and Lizahrd plates can only be triggered by players, the yellow plates can only be triggered by NPCs and enemies, and red and green plates can be triggered by anyone. If camouflage is needed, simply recoloring them with paint is effective enough. Additionally, pressure plates can be welded into minecart tracks at an anvil, yielding Pressure Plate Tracks, which can then be activated if a player rides a mincart onto them.

Weighted Pressure Plates: These are similar to normal pressure plates, with one key difference: they send a second impulse after the player steps off of them. In some cases this can function as an on/off switch, whereas in others it will cause an action to be performed twice. They come in different colors as well, though all colors function identically, and can only be triggered by players.

Pressure Pads: The pressure pad only comes in one color, and sends an impulse down a wire when struck by a projectile. Unlike other pressure activators, it can be placed on side walls, as well as the ceiling. The pressure pad has some fairly novel uses, which will be explained later, but it is worth noting now that some unusual entities, such as yo-yos, spear trap spears, flails, and fishing rod bobbers, are considered projectiles and can thus activate the pressure pad.

1/3/5 Second Timers: Timers give off an impulse at regular intervals, denoted by the name of the timer. Timers are themselves subject to impulses, and can be triggered on and off by wire, as well as manually toggled by right-clicking.

Gem Locks: Each gem type (including amber) has an associated gem lock. The lock is placed on backwalls, and emits an impulse when the appropriate gem is placed inside. By placing the requisite large gem in a carefully located chest, these can be used as a simple means to control progression.

Trapped Chests: A trapped chest will send an impulse whenever someone attempts to open it. The superficial value in pranks is obvious, though they can also be used to open secret passages, and the like. Though TEdit is capable of placing locked trapped chests, these don't require a key to function.

Logic Sensors (Day/Night): Sensors are placed on backwalls and send an impulse when their conditions are met. Day Sensors send an impulse at 4:30 AM in-game time, once per day, and Night Sensors send an impulse at 7:30 PM, once per night.

Logic Sensor (Player Above): This sensor sends an impulse when the player enters an area above it, and another when they leave the area. The exact size of the area can be seen using wire tools. It is worth nothing that this area is not perfectly aligned with blocks, and actually extends a few pixels farther than it might superficially appear. In this image, for example, the area appears to be approximately ten tiles high, but is in fact ever so slightly taller than that, allowing the mechanism to be toggled by a player standing on top of the trap door, thus opening it.

Liquid Sensors (Water, Honey, Lava, All): Liquid sensors send an impulse upon contact with their respective liquid types, and send another impulse upon losing contact with the liquid. If a sensor is fully submerged in a compatible liquid, it will not continuously activate, but it will do so if liquid is repeatedly poured over it. One could create a perpetual motion machine by placing a compatible liquid sensor in the path of liquid flowing through an inlet/outlet pipe system that is triggered by said sensor, though liquid starvation or duplication, or exiting the world could still break the cycle, not to mention that a timer would more easily and precisely complete the same task.

Useful Target Mechanisms:
Actuators/(In)Active Stone Blocks: Actuators are placed inside of blocks, and toggle said blocks' solidity upon receiving a wire-based signal. Actuated blocks will become pass-through, allowing liquids and most solid objects to go through, though sand will not fall through. Inactive blocks can be visually identified by the fact that they are transparent and darkened in color. The Inactive and Active Stone blocks are stone that possess actuator properties inherently. Curiously, they cannot be infected by Corruption, Crimson, or Hallow, and if they are turned inactive after being sloped by a hammer, reloading the world in this state will cause them to become unsloped.

Inlet/Outlet Pumps: Upon receiving an impulse, inlet pumps drain liquid that overlaps them, and send that liquid to an outlet pump connected by wire. Each activation can move up to four blocks of liquid per pump, though multiple pumps can be set up on each side via the same set of wires to increase the transfer rate. Extensive use of pumps can sometimes lead to liquid duplication, especially when the inlet pump(s) are submerged in deep liquid. Outlet pumps will not function if they are fully submerged.

Traps: Traps can be used to attack the player by sending an impulse to them. The most straightforward way of doing so (as occurs naturally in-game) is to wire one to a nearby pressure plate. Each trap functions differently (except the super dart trap, which simply deals more damage than the normal version). Projectiles launched from traps (including the spear trap's spear) can trigger pressure pads, and thus have a use in 'under the hood' mechanisms, as well. For this purpose, spear and dart traps are generally the most useful for having the highest rate of fire and longest range, respectively. For some reason, spear traps can't seem to hit pressure pads in a one-block hole, and require a firing lane of at least two blocks in order to do so.

Statue Mechanisms: A number of statues will perform a certain function, usually spawning a creature of the same type as the statue itself, if triggered by a wire impulse. A list of eligible statues and their effects can be found here: https://terraria.wiki.gg/Statue

Teleporters: When a teleporter receives an impulse, it will transfer any players, NPCs, and enemies standing within a 3x3 area above it from one teleporter to the other on the same circuit. For best results, do not place more than two teleporters on the same circuit; it is permissible to place one teleporter on multiple circuits by using different colors of wire, however. Teleporters can be hammered flat and sloped like normal blocks, and flattening one will slightly flatten the 3x3 teleportation area above it, as well. Because the teleportation area extends up three blocks, one can place the teleporter two blocks under the ground, and still teleport something standing on the ground above it.

Explosives: When triggered by a wire impulse, explosives, well... explode. This explosion can dislodge most block types, and as such should be used sparingly on adventure maps where digging is prohibited. Careful use of these devices can be used to open up new passages for the player, however. The radius of the explosion is ten tiles, and immune blocks include hardmode ores, dungeon bricks, and Lihzahrd Bricks. An exact picture of the blast radius can be seen on the Terraria wiki here: https://terraria.wiki.gg/File:After_explosion.png#filelinks

Aesthetic Mechanisms: Some mechanisms, such as light sources, bubble machines, music boxes, and water fountains (which change the color of nearby water) can be triggered by a wire impulse, but provide effects that do not directly influence gameplay. While these may be useful on an adventure map, there is no need to discuss the specifics of their individual functions.

Announcement Box: The announcement box can be used to send global messages that appear in the same manner as boss awakening messages, event warnings, etc. Well placed messages can be useful in setting the mood, and dropping tidbits of plot on the player. While the sign can be read directly, it will trigger a global message if activated via wire, and can thus be safely placed well off-screen. The color of the text in these messages can be modified, and they can be made to show items as well. Instructions for doing so can be found on the Terraria Wiki here: https://terraria.wiki.gg/Announcement_Box#Formatting

Logic Gates: Logic gates are complex mechanisms that serve to activate other mechanisms. Basic instructions on their use can be found on the Terraria Wiki can be found here: https://terraria.wiki.gg/Logic_Gate

Limited or Single-Use Mechanisms
One rather simple, yet non-default technique that can be applied is a single-use switch. Normally, when a switch is flipped (or another activating device sends out an impulse), anything on the circuit will receive an impulse. The switch might, for example, actuate some blocks to open up a passage forward. However, it may sometimes be desirable to prevent a circuit (or at least certain parts of it) from being triggered more than once. In my adventure map, there is a puzzle-heavy area that at one point requires multiple puzzles to be solved before the player can progress. In some cases, the conditions for solving the puzzles can be undone accidentally, and it would be preferable to prevent this from happening, but how could this be achieved?

This task can be easily accomplished through the use of an eligible trap, an actuator, and a pressure pad. Rather than hooking up the circuit directly, the single-use portion of the circuit is wired to the trap, which then activates the pressure pad, which is wired to the other end of the circuit. A transparent block is placed in front of the pressure pad, and the pad is wired to it, as well. This blocks the pressure pad from receiving additional input, permanently disabling that portion of the circuit, unless an outside mechanism makes the block transparent again.

The circuit thus operates in the following way:
1. The initial trigger is activated. (lever is pulled)
2. The impulse from the initial trigger activates the trap. (dart trap fires a dart)
3. The trap activates the secondary trigger. (dart hits teal pressure pad)
4. The secondary trigger activates the target mechanism, while simultaneously disabling itself by solidifying a nearby block, preventing the trap from activating it again. (Pressure pad activates above flame trap, and turns block inside solid. Because block is now solid, dart cannot hit pressure pad any more, and thus the mechanism can no longer activate.)

In this example, the target mechanism is a flame trap.

There are a few more things worth noting with this mechanism. Firstly, darts from dart traps spawn two blocks ahead of the trap, rather than directly adjacent, so the actuated block should not be directly in contact with the trap in that case, as the dart will simply spawn ahead of it. Placing a single solid block in front of the dart trap can be a useful visual guide. Also, as I implied, this setup can be used to make part of a mechanism single-use, while allowing other portions to be reused. If, for example, one wanted a message to play the first time a teleporter was used, the teleporter could be wired normally, with a trap in the same circuit, and then the pressure pad in line with the trap wired to an announcement box.

Limited use mechanisms can be constructed by this same general principle, albeit with a greater number of layers. Multiple lanes with teal pressure pads can be used, each slightly longer than the last, with all but the first initially sealed, and each pressure pad unsealing the lane below it while sealing itself. In this way, each successive lane is opened by the one before it, and the mechanism continues to function due to all traps firing at once. However, once all lanes have been exhausted, the mechanism will no longer function. When a large number of uses are required, multiple columns of lanes can be used. Each time the final pressure pad of the primary lane is activated, the secondary line fires, and all of the pressure pads in the second lane reset the first lane by actuating the block in its initial row. This makes the total uses the multiplied total of the number of lanes in each column. A tertiary lane can be added, as well, and scaled up indefinitely with quaternary lanes, etc.

In this example, the mechanism is wired to toggle the chandelier above with every activation, and to activate the flame trap below only on the final activation. One could even have a completely unique effect with every activation by wiring each pressure pad in turn to separate mechanisms.

On a semi-related note, such a setup could be wired to grouped torches, and used as a counting mechanism.

One potential issue with this setup is the fact that traps have cooldowns, and thus there is a limit to the frequency with which the mechanism in this scenario can be activated. With the shortest cooldown, the spear trap is usually the best choice, unless the firing lanes are extremely long.

Timed, Delayed, and Self-Regulating Mechanisms
Timing can be a very important part of the operation of mechanisms. On its most basic level, traps might be wired to a timer, such as a 5-second timer, to regulate their firing rate. However, much more advanced uses exist.

For example, it may sometimes be desirable to delay the activation of a mechanism, or the activation of a secondary effect of the mechanism. One application of a delayed mechanism is to have traps in a room activate the moment after the player enters, forcing them to quickly move out of the way, but giving just enough time to react. Another use is having a mechanism actuate blocks in a pathway up ahead, and then close them after a certain amount of time has passed, requiring the player to quickly reach the door in order to pass through. In the first case, the activation of the mechanism's primary effect is delayed, whereas in the second, its secondary effect (i.e. making the blocks solid again) is delayed.

There are a couple ways to delay a mechanism, but they all rely on the same general principle. In order to delay a mechanism, the initial trigger must activate that mechanism only indirectly. The initial trigger activates another mechanism whose primary purpose is to activate the delayed mechanism. If desired, one can wire an effect to be activated immediately (such as a message from an Announcement Box telling the player to hurry forward), by connecting it to the initial trigger, as well.

The method by which the indirect mechanism activates the delayed mechanism varies by setup. One straightforward way of accomplishing a delay is to hook the initial trigger to a dart trap firing down a long tube towards a pressure pad. Darts spawn two blocks ahead of their respective dart traps, and travel at 45 blocks per second, thus allowing fairly precise timing of the secondary mechanism's activation, depending on the length of the tube. Darts travel at 50% speed in water, and 25% speed in honey, so liquid can be used to reduce the required length the tube, if need be. Note that darts can only travel for one minute before breaking, so with extremely long delays, a secondary dart lane, activated by the pressure pad in the first, may be required.

Counting the second block after the dart trap as the starting point, the pressure pad's location should correspond to when you want it to be triggered in the following way: (t*45)/L = distance in blocks from starting point, where t is time until activation (in seconds), and L = 1 for no liquid, L = 2 if there is water in the whole tube, and L = 4 if there is honey in the whole tube. If one wanted to activate a pressure pad in 1.58 seconds, with water in the tube, then it would be (1.58*45)/2 = 36 blocks long. Note that activation times using this method must always be rounded to the nearest 45th of a second.

A mechanism can have any arbitrary number of moving parts (e.g. a setup with staggered trap activation), all of which can be wired to a different trigger in sequence. A dart can be fired down a long lane, lined with pressure pads, each of which are wired to a different target mechanism. If activations are staggered, but continuous, each pressure pad can instead be wired to a timer, which is in turn wired to the target mechanism.

In the above example, pulling the lever activates the dart trap, which fires a dart down the lane, striking pressure pads, each of which are wired to nearby timers. The timers activate rows of spear traps, and because their initial activation was staggered, so too will all subsequent activations be. This exact setup wouldn't be of much use on an actual adventure map, as the spear traps can't hit anything, but the same general principle can be used in myriad setups, with any number of mechanisms wired to each pad.

Another method is to wire the initial trigger to a timer that turns itself off after one activation. This can be achieved by wiring the timer to a trap, which activates a nearby pressure pad, which is in turn wired to both the timer (deactivating it) and the secondary mechanism.

In this example, the lever turns on a five second timer, and activates a primary mechanism off-screen. After five seconds, the timer activates a dart trap, which shoots and hits a pressure pad with a dart. The pressure pad then deactivates the timer, and activates the primary mechanism a second time.

If you wish for the mechanism to run multiple times, but not indefinitely, this setup can be layered, with the timer activating a finite-use mechanism each time, albeit with the final activation turning off the timer, and if desired, opening the first dart trap's firing lane again, allowing the mechanism to be reused.

Automatic Events
Sometimes, rather than preventing the player from activating a certain mechanism at a certain time, one must prevent a player from not activating a mechanism at a certain time. It seems simple enough to rig a player above sensor to one's mechanism, and force the player to walk through it, but as the player passes outside of the sensor, it will trigger a second time. With enough ingenuity, many such mechanisms can be broken, allowing improper passage. Another thing to note is when the mechanism in question is nowhere near the player, such as if one wises to run an event when the maps loads. Despite these apparent difficulties, constructing robust mechanisms of this nature is surprisingly straightforward.

Firstly, there is the start-of-map event. Perhaps a minor cutscene of some sort plays (more on that later) or whatnot. Regardless of your intent, there is a very simple way in which to activate a mechanism when the map is loaded for the first time. Simply place a liquid sensor in a box as the trigger for your mechanism, and place some compatible liquid in the air above it using TEdit. When the map is loaded, one of the steps for preparing the world is "Settling liquids", which will cause the liquid in question to be immediately placed on the sensor, activating the mechanism the moment the world loads. In fact, since sensors placed in TEdit are off by default, it may not even be strictly necessary to place the liquid above it, as it will activate immediately even if it is already submerged in liquid, so long as it is off when the map loads... usually. Small quantities of liquid can be finicky here, so it's best to test it first. Since the liquid isn't going to be flying into the air anytime soon, this sort of trigger is naturally a single-use mechanism by default; activating a mechanism every time the map starts is much trickier. In this example, the honey settles once the map is loaded for the first time (this screenshot was taken in TEdit), triggering the liquid sensor, which displays a message via the Announcement box on the left, and fires a dart. A second message is then displayed once the dart hits the pressure pad on the right, which is wired to the Announcement Box on the right.

A more limited example involves a mechanism activating when the player enters the appropriate region. For example, if there is a temple filled with traps that are running on a timer at all times, it would not only be easier on the builder, but easier on the player's computer processor to only have those traps run while they are actually inside the temple. In order to do that, a checkpoint must be built. The traps will be active when the player passes through, thus ensuring that they function as intended.

With this checkpoint, no matter what alignment the mechanism is in, it is impossible for the player to pass through, as one of the two gates will be solid, blocking entry. When the mechanism is active, however, the gates will alternate between solid and actuated states due to the activity of the one-second-timer. This allows the player to pass through both gates, one at a time, during their respective actuated phases, but only while the mechanism is active. Simply wire the gate to the timer you are using run the desired mechanism(s) continuously, and the player will be forced to keep the mechanism running in order to enter the area. The only ways to defeat this are if the player pulls the lever again after passing the first gate (be sure to put the lever out of reach), or if they use the Rod of Discord... but surely the R.O.D would be banned on an adventure map, right?

An alternate form of this checkpoint involves the use of hoiks. The player activates the mechanism, and then stands in the spot circled in the diagram. The block in that spot alternates between solid and pass-through when the mechanism is running, allowing the player to stand there, and then be subsequently forced through the hoik. If desired, a second, backwards hoik can be constructed to allow the player to leave through normal means.

Now, if one absolutely must have an event run on map load every time the map is loaded, a mechanism like the above could be placed around the map's spawn point(s), requiring the player to activate the mechanism before they can leave. It's a bit intrusive, but mostly foolproof. Another way of doing it, if the map contains no beds for additional spawn points, is to place a teleporter in a sealed box just under the world spawn point, with a pressure plate hooked up to it. The player will fall a short distance upon starting the map, landing on the pressure plate and teleporting outside of the box. Then, hook that plate to the trigger for your mechanisms, and this will ensure that they run continuously. It is possible to create de facto additional spawn points by wiring the teleporter to a mechanism that permits for multiple destinations. By meeting certain criteria, one could reroute the teleporter to another area. However, such a thing would require extremely complex wiring, and is not strictly within the bounds of this guide. Alternatively, a much simpler solution would be to have the initial teleporter lead to a hub room with various sealed teleporters leading to various designated 'spawn' points. Each teleporter would have solid blocks barring passage to them, with those blocks being actuated upon meeting certain conditions, such as pulling a lever near their respective teleporter's destination.

One word of caution: if you run too many spiky ball traps in the same world, some of them may produce underwhelming results, due to the limit on active spiky balls in a given world.

In the case that one wishes to run a mechanism only once at a given point (such as displaying a certain message via announcement box after passing through a certain region), then a player above sensor wired to a single-use mechanism will suffice.

Progression/Equipment Checks
Unless your adventure map is beyond linear, you'll need more ways for players to progress than simply walking forward in a straight line. Having a switch to pull that opens up a path forward is one very simple way of accomplishing this, but this solution is sometimes impractical, or even simply too bland. A more natural way to control player progress involves equipment checks. By granting players a certain piece of equipment, they can then use it to surmount an obstacle (whether that be literally, or metaphorically).

One advantage of equipment checks is that it allows for progression checks other than 'reach point A and pull a lever.' Another advantage is that these progression checks can sometimes be used as puzzles in and of themselves. Upon receiving a certain piece of equipment, the player might then be put to the task of figuring out where and how it could potentially be used to aid in progression. Lastly, this form of progression check is often more natural than the alternatives, which might otherwise require the map creator to explicitly state the progression conditions in the rules!

Below is a list of methods through which the player can obtain progression items, and below that, potential ways to use items in progression. Note that some of the methods of obtaining these items, such as purchasing from a merchant, may be undesirable, and thus be disallowed in the rules of a map. Be sure you are aware of all of the ways in which relevant progression items can be obtained, lest you unwittingly leave open the possibility of the player acquiring such items through unintended means.

Some items are obtained via treasure chest only (as any item can be obtained via chest on an adventure map.) This makes it very easy to control when the player can acquire them, but also prevents them from be acquired in a more natural way.

Other items are obtainable via crafting. If crafting is allowed on your map, careful control of which crafting materials and stations can be obtained will allow you to customize which items the player can craft at any given time, and by extension what sorts of progression items they may obtain. Items that can be crafted, but require other items of their kind (e.g. a gun that can only be crafted using a similar gun as a material) should not generally be considered a separate item. Be aware that some slimes are capable of dropping ore 'bonus' drops, which may need to be accounted for in the map rules.

A small handful of potential progression items can be obtained from the environment. This generally requires that environmental items, such as Shadow Orbs or Crimson Hearts be explicitly placed by the map creator, but there are a few exceptions, such as potion materials growing freely on certain surfaces, and certain items being obtainable via fishing.

Others still are dropped by enemies. This can be the trickiest sort of progression item to work with, as one does not generally want to force the player to grind for an item to progress, nor would one want an enemy to hand the player a progression item early. For normal enemies, the use of certain drops may need to be regulated in the map rules. In the case of bosses, however, this can be of great use. Be aware that most bosses don't drop progression items directly, but merely the materials required to craft them, such as the Eater of Worlds dropping the materials required to craft the Nightmare Pickaxe.

Some progression items can be obtained from an NPC. Controlling which NPCs the player can access can be useful, though explicit rules may need to be made in the case of the Travelling Merchant, as he appears at random, and is capable of selling potential progression items.

Walls:
Basic walls can be scaled with most mobility enhancers, depending on height. Taller walls will eventually require Shoe Spikes, Climbing Claws, or their upgrades. Walls with alternating empty blocks cannot be climbed in that way, but can still be ascended via grappling hook.

Barring the use of a grappling hook, the heights of climb-proof walls can be specifically tailored to the exact jump-enhancing accessories that are required for the check. Be sure to test the height of the jump with the items in question, and adjust your wall accordingly. Using a tall backwall, or a temporary ice block from the Ice Rod as an anchor, one can place a block upon reaching the top of the jump, to quickly get a rough estimate of the desired wall height.

If grappling hooks are not restricted in the map or its rules (hooks can be dropped from ordinary skeletons), it can be difficult to discourage players from abusing them. Making a surface out of alternating wooden spikes and burning blocks (e.g. Hellstone Brick) is one possible method, though it isn't particularly elegant, and may not kill the player if the wall isn't tall enough. If one is feeling particularly vengeful, lava can be added in a tall one-block column, contained by a bubble block wall. Even if the player has lava protection, it will still reduce movement speed, just be aware that players can swim in lava using flippers and their upgrades.

A swimming check can be implemented by suspending a tube of water between bubble blocks, allowing the player to swim up it and over the hazard. This can be combined with a lava protection check if the tube is filled with lava instead.

Teal pressure pad setups (basic-advanced):
Teal pressure pads can be wired to blocks with actuators to open pathways, among other things. While the most basic form of this progression check, having a pad out in the open, can be surpassed by any projectile, more stringent checks are possible.

One possible setup is something I call a 'Meteor Lock'. The player fires a bullet of Meteor Shot into the shaft at a specific angle, and it ricochets to hit the pressure pad at the end.

The shaft is built to such a length so that yo-yos cannot be forced through it. If one also needs to disallow controllable projectiles, a pressure pad can be placed on the ground between the two curves, wired to a timed mechanism that briefly deactivates an actuated block at the end of the shaft. The bullet will travel faster than the controllable projectile, and hit the pressure pad before the block becomes solid again. The exact speed required of the actuating mechanism varies depending on the length of the shaft, and should be manually tested.

As their exact usage is not immediately obvious, explicit instructions on the firing angle can be included on a signpost in-world. Activation instructions are as follows: 1. Stand on the top platform inside the mechanism
2. Move as far to the side opposite the platform (near the tube) as possible 3. Align the tip of your cursor with the pixel on the near edge of the inner meteorite brick, diagonally up between the second and third pixel from (and including) the bottom corner, on the long edge. 4. Fire Meteor Shot

<- This image shows the exact spot where you need to shoot.
Note that a gun is a guaranteed drop the first time a Shadow Orb or Crimson Heart is broken in a world, so a Meteor Lock can be used as a check for that.

Another setup is to have the pressure pad in a place where only a yo-yo can reach. By threading the yo-yo through the maze, one can strike the pressure pad. Due to the finite range and throw duration of most yo-yos, one can even create longer mazes that require yo-yos with longer range, etc. Bear in mind that the white string and its alternates increase yo-yo range, and can be crafted at a loom from cobwebs. Accessories that increase melee attack speed also increase yo-yo range, throw duration will remain a significant factor in ability to clear such a mechanism. Yo-yos struggle to fit through a one-block hole, but can more easily fit if the entrance is two blocks wide, as in the example image. The example is combined with a single-use mechanism, as one likely wouldn't use a yo-yo maze for something that was intended to be activated multiple times.

Be sure to test prospective mechanisms with the desired yo-yo to be sure that players can realistically reach the end in time. This example has two holes, the bottom of which is too long for most yo-yos to reach the end from.

The Magic Missile, Flamelash, and Rainbow Rod fire projectiles that can be manually controlled, and can thus be substituted for yo-yos in these cases. One can also construct a maze that can only be cleared by a controllable projectile, due to their increased range compared to yo-yos. It should be noted that the Flamelash's projectile will dissipate upon contact with water or honey, and so a maze can be filled with either of these if one wishes to disallow the Flamelash from clearing it. The Flying Knife can also be controlled to move through such mechanisms.

The above setups use a weighted pressure plate in conjunction with actuators to prevent the player from walking around the mechanism to thread a yo-yo through (though most yo-yos would have insufficient throw duration regardless). The water between the bubble blocks acts to restrict use of the Flamelash for this particular setup.

A few even more niche setups also exist. For example, one might make a checkpoint similar to the one outlined in the previous section, but instead of using a timer, a pressure pad is placed in a sealed area. A cloud from a Crimson/Nimbus Rod could be shot into the hole, repeatedly toggling the mechanism and allowing passage.

Training dummies can be placed in pressure pad setups to block non-piercing projectiles, though unless a map is entirely indoors, the ease of obtaining fallen stars to craft Jester's Arrows will render them easily surpassed in most situations.

A grenade check can be created by wiring actuated floor blocks to a weighted pressure plate, and placing a pressure pad in a shallow hole at the end. Bouncing a grenade off the high end of the wall will allow it to fly in the other direction, and strike the pressure pad. This setup can still be activated by a yo-yo or controllable projectile, but placing the pressure pad in a hole should prevent Meteor Shots from hitting it. Conveyor belts do not influence the movement of thrown grenades.

Speed Checks:
The idea behind a speed check is simple: hit a trigger that opens the path ahead, and wire it to timer (or series of them) to close the path if the player doesn't reach it in time. To prevent cheating, a checkpoint can be wired with a barrier before the speed check that closes if the second barrier is open. These can be used for an obstacle course, or simply to see how fast the player can move. As certain mounts (including minecarts) and accessories can increase movement speed, these can be used as progression items in such a fashion. By their very nature, speed checks are inherently delayed, self-regulating mechanisms.

Be aware that grappling hooks can also be used to increase speed indirectly by grappling the floor at an angle. Placing a large number of platforms in the area can catch the grappling hook, and inhibit this method.

The basic wooden minecart has a max speed of 37.4 blocks per second, the metal minecart a max speed of 48.4 blocks per second, and the Mechanical Cart a max speed of 75 blocks per second. Keep this in mind when designing minecart speed checks, as a check for the metal minecart should be between 38 and 48 blocks in length, and on for the mechanical cart should be between 49 and 74 blocks in length. The time to accelerate must also be considered, though a few booster tracks before the check can alleviate the need for extra space. Lastly, if one reaches the one-block gate as it solidifes, it will still be possible to pass through, so the check will need to be slightly longer than noted above.

As mounts generally increase the player's height off the ground, using a three block tall hallway can restrict their use, and force the player to rely on other mobility enhancements to get through.

Other:
The ability to safely pass through/walk over lava or burning blocks can be used as a check.

A certain cumulative HP/Defense total can be used as a check if a three block high hallway is made with spikes or wooden spikes as the floor and ceiling. This can also be used as a hybrid speed check, but if a hoik made of spikes is constructed, then speed can be rendered irrelevant. Bear in mind that hoik movement is extremely fast, so the check hoik will likely need to be quite long.

Downward hoiks incur fall damage normally, so a long one can be used as a check for fall damage protection. Be aware that down hoiks can be somewhat finicky; if the player enters too quickly, they might get stuck, or fall out the sides. If desired, one might construct shafts beside the hoik, lined with rope, so that the player can climb back up and try again should they be forced out. Try experimenting with different types of hoik to see which is best for your purposes.

Demon/Crimson Altars can be used as checks for entry into hardmode... assuming you're willing to allow some ore and infection to spawn in the world when one is broken. A door can be sandwiched between two altars, for example, preventing it from being opened until one of the altars is destroyed. Also, blocks cannot be actuated when an altar sits atop them, so destroying said altar can allow one to open a passage with a nearby switch. This all, of course, requires that the player picks up the Pwnhammer after defeating the Wall of Flesh. Alternatively, if the map begins in hardmode, the hammer can simply be placed in a chest somewhere.

Certain formations of blocks, such as those in the image on the left, can only be passed through by firing a grappling hook into the hole, making them potential checks for a grappling hook. For more info, see the "Miscellaneous" section.

Grappling to an overhang block and jumping will allow passage through a one-block hole or platform, and can be used as an alternate form of the check, though such checks may not be intuitive to all players, and this function of hooks may need to be hinted at or explicitly noted by the map-maker at some point.

An obvious, yet quite useful progression check, is to allow players to mine through certain ores and hard materials (e.g. Desert Fossils). This is an extremely straightforward way to make a check for pickaxe power.

Terrain Restructuring
Flipping a switch to actuate some blocks is one thing, but sometimes that just won't cut it. Whether one wants an extremely dramatic change in the scenery, or simply a more unique one, there are other ways to change the terrain, which may or may not require a wire trigger.

Excavation via explosives:
One of the most obvious (and least subtle) ways to change the terrain is to wire some explosives to a desired trigger. Once the trigger is activated, the explosives will punch a hole through the terrain in the desired area.

There are a few things to pay attention to when using this method. First, mind the blast radius. If you aren't quite sure how many blocks the explosion will take out, you can save, test the explosion, and then exit the map without saving to reset it. One can exit without saving by using the Task Manager, or simply clicking the red X on the taskbar icon below. The second thing to be aware of is explosion-proof blocks. These include dungeon bricks, Lihzahrd bricks, hardmode ores, and Hellstone (while in pre-hardmode only). These blocks will not dampen the blast radius directly, but they can be used to de-facto reduce its effect by replacing nearby blocks you wish to retain with explosion-proof ones. Lastly, be aware of the fact that the blocks in question will not be totally obliterated, but instead dropped on the ground. If the player travels to the area of the explosion, they can potentially pick the blocks up. If this isn't a problem, it can be ignored, but if it is, a secondary explosion can be triggered a moment after the first one (such as via a dart fired through a tube with two pressure pads) in a remote location. There is a limit to the number of loose items on the ground, so if the secondary explosions destroys 400 blocks or more, then the dropped blocks from the initial explosion(s) will despawn. One could also place a pool of lava underneath the targeted blocks, so they will fall into it and be destroyed, but this may be impractical, for obvious reasons.

Sand manipulation:
Less extreme restructuring can be performed by utilizing the gravity-obeying properties of sand (and by extension, silt and slush). One obvious approach is to use explosives in conjunction with a block type that is affected by gravity, knocking out the supports under it, and thus causing it to fall. While this is functional, it is sometimes less than elegant.

A cleaner way to manipulate sand is via cobwebs. Cobwebs can be used to suspend sand blocks, and when they are dislodged, the sand will fall down. This can be accomplished manually if the player can reach the cobwebs with a weapon, or traps can be wired to destroy the cobwebs upon satisfying the desired conditions. All liquids are also capable of dislodging cobwebs. Unlike with explosions, the manipulation of the sand can even be made to safely occur before the player's eyes. The cobwebs in the screenshot on the left were painted with shadow paint for visibility.

It is worth noting that gravity-affected blocks are completely destroyed if they land on top of minecart tracks.

Liquid manipulation and destruction:
Moving liquid with pumps is relatively straightforward, but it can be time-consuming for large quantities, and requires flat ground on which to place the pumps. Under certain circ*mstances, a much faster alternative can be found in simply actuating blocks to pour water through a hole. Water can be added to an area by hiding it in a wall, or the ceiling, and actuating alternating, one-block tubes to pour out a large volume at once. While cobwebs cannot hold back water, sand suspended upon cobwebs can do so. If one does not mind making a large hole into which it can go, this can also be done on the floor to quickly drain a liquid. Alternatively, the tubing can exit somewhere else, transporting the water to a desired (downstream) location. Even if the player immediately exits the world, the setup will not break, as the water will be settled automatically upon reloading the world. It should be noted that pouring large volumes of liqud through a small hole, or pumping liquid from the bottom of a deep pool can result in liquid duplication, which brings me to my next point.

If you should desire, it is possible to totally destroy water and honey via a very easy and simple method. When any liquid contacts another type of liquid, a certain type of block is formed, and one block's worth of each liquid involved is destroyed. If a solid object is already occupying the space, however, the block cannot form, but the lower-priority liquid is still destroyed. Liquid priorities are as follows: water < honey < lava, hence why lava cannot be destroyed via this method. Since lava will destroy most things, and covering it in blocks is, of course, not an option (unless you wish to destroy lava by smothering it with sand and reloading the world), there are only a handful of things that can serve our purpose here. Natural background objects, which can be placed in TEdit, are among them, as are wooden beams.

The pictured setup (visually condensed) contains a mechanism for contained water duplication. Pouring the water through the small spaces between bubble blocks quickly leads to duplication, raising the overall water level. Wooden beams are submerged in the lava on both sides, leading to the complete destruction of any water that spills over the side, with an extra block on the end as a fail-safe. Small lava holes like those can be used to limit the height of water/honey in a room, or prevent it from running off into a certain section of the room, protecting against runaway liquid duplication. It should be noted that outlet pumps will not function if they are completely submerged in liquid, so if placing the pump itself at a lower elevation is not an issue, and the pump does not need to run continuously, the pump can be positioned such that its upper half aligns with the maximum permissible depth of liquid in the room.

Liquids can also be used to destroy certain non-liquids, such as any liquid dislodging cobwebs and most torches, and lava destroying most furniture and platforms, as well as burning away foliage.

Less destructively, water or honey can be poured from above by environmental or mechanistic means to create a path of solid blocks over a lava pool below.

Enemy Spawn Manipulation
There is no hard-coded way to directly control what kinds of enemies spawn in a given area, or how frequently, but there are a number of things that one can do as a map-maker to influence enemy spawns nonetheless.

Firstly, it is important to have a working knowledge of how enemies spawn. For more info, you can look at this shameless plug here: https://forums.terraria.org/index.p...afk-farming-every-biome-simultaneously.54779/

The section "Biome Requirements (and how to meet them)" discusses how to induce the presence of a given biome. This can also affect the background and music, and so has an aesthetic use, as well as a use in manipulating what kinds of enemies spawn. The section "Enemy Spawning Requirements" goes into more detail on the exact conditions under which certain enemies spawn. Changing to a certain biome does not inherently guarantee that all, or even most spawns will correspond to the given biome, so certain techniques, such as manipulating spawn surface, can be used to control what types of enemies spawn, somewhat independently of biome.

Manipulating what types of enemies spawn is only one piece of the puzzle, however. Manipulating the rate of enemy spawn can be used to control the difficulty of a given area. Peace Candles and Water Candles can be used to decrease/increase the local spawn rates, respectively. You'll need to place them at regular intervals in order to cover an entire region. According to the wiki, Peace/Water Candles have an area of effect with a radius of 48 blocks. This means that placing the desired candle type at horizontal and vertical intervals of 96 or fewer blocks should result in total coverage.

These should ideally be placed inside of walls, so that they cannot be removed, and smothered with honey or water to reduce their light levels (this will not dislodge them.) Under normal circ*mstances, they can only be placed on certain surfaces, such as platforms however they can be placed anywhere in TEdit. Candles placed on invalid surfaces (such as directly on blocks) will be dislodged if something nearby is altered. For example, if Corruption spreads to the block on which the candle sits in hardmode, then the newly infected block will dislodge the candle. This can be used to deliberately (and permanently) deactivate the candles upon starting hardmode by insulating the area, and placing one infected block adjacent to the one on which the candle sits. Once hardmode begins, the infection will spread to the adjacent block (and that block only, due to the insulation), dislodging the candle. Candles can also be (permanently) disabled via wiring by actuating the block beneath one.

Here is an excerpt from my aforementioned guide: "When choosing where to spawn an enemy, the game will select an empty tile that does not have player-placed backwalls on it, and spawn the enemy on the ground below that point. Enemies will spawn a minimum of 63 tiles to the left or right of you, and a maximum of 84 tiles. The chosen tile will also be between 35 and 47 tiles above or below you." This knowledge can be used to manipulate spawns in a few ways. First, holes in the walls (preferably a little ways off so that players cannot see them) can be used to contain enemy spawns from a distance, de facto reducing the number of enemies that spawn in areas the player can actually traverse. Wide-open areas are naturally supportive of the full spawn rate, which often results in a larger de facto number of enemy encounters underground than one would expect from the normal game. Using these wall holes can therefore cut back on that. Conversely, tight spaces naturally restrict spawns. Digging tall shafts, one block wide, will allow the game to select those areas as spawn points, simply spawning something underneath. This does not increase the size of the actual spawning area, but does make it much easier for the game to find a valid spawn spot, de facto increasing spawn rates.

While Water/Peace Candles cannot be toggled with wires (as of this writing), the secondary methods of spawn control can. Use inactive actuated blocks inside of your wall holes to restrict/enhance enemy spawns, and fill them in by toggling the blocks with wire to remove the effect. This could be used, for example, to de facto increase the spawn rate in an area when revisiting it later in the game. One could even use both techniques, starting with the vertical pillars filled, and the wall holes open, and reversing them to give an even greater relative increase in spawn rate.

Player-placed backwalls can also be used strategically to restrict enemy spawns. Empty tiles where such backwalls exist cannot be selected by the game when spawning enemies, so if player-placed backwalls extend to the ceiling in an area, enemies will be unable to spawn in those areas. One could instead only place patches of backwall to de facto reduce spawns without eliminating them completely. This is especially effective if a given player-placed backwall is nearly identical to a natural one, allowing it to be visually blended with its natural variant, if desired. Stone backwalls are capable of being naturally infected in hardmode, and can thus lose their ability to restrict spawns. Inducing this to occur automatically on an adventure map can be somewhat difficult, however, as not only will it likely lead to the entire region being infected if one is not exceedingly careful, but there is also the fact that the walls themselves cannot spread infection, and thus only backwall within three tiles of infected blocks will be turned.

Another way to balance enemy difficulty is by placing out enemy banners of those enemies you wish to nerf for a given region. According to the wiki, they are effective within a radius of 50 tiles, so placing one every 100 or fewer tiles should allow for full coverage in a region.

Enemy statues can also be used to encourage confrontations. They can be wired to nearby triggers, or hooked up to an automatic mechanism to continuously spawn foes.

Miscellaneous
A one-way passage can be easily created without the use of any wiring by simply putting a one-block step up in a hallway with a low ceiling. Make the ceiling three blocks tall in all places aside from the step up, where it is four blocks tall. When the player steps up, they will be unable to go back down the same way they came. Note that this passage can still be defeated by firing a grappling hook diagonally through the hole. Curiously, it is possible to make it though such a passage that rightward travel by sprinting through it with running boots, but it is not possible to do so through one that bars leftward travel.

A few well placed blocks, in conjunction with a weighted pressure plate and actuators, can defeat even the best of grappling hooks, though it should be noted that the weighted pressure pad setup works equally well in a straight, three block tall hallway.

Note that if the elevated block or the ceiling above it are sloped appropriately (as shown in the bottom two examples), then the player can walk through both ways, unimpeded.

A flail course can be constructed by creating a hole in the ground with actuators and a weighted pressure plate, and then putting a pressure pad at the end. Unlike most yo-yos, flails can be held out indefinitely, and unlike most controllable projectiles, they won't dissipate on contact with a solid object. Thus, a somewhat unique check, or even obstacle course can be created by designing a setup for a flail. Since flails have limited range and are affected by gravity, these factors must be taken into account when designing such a course. The flail is thrown through the hole while standing on the weighted pressure plate, and threaded through a passage below the floor until reaching the pressure pad at the end. This can be used in an obstacle course of sorts, so long as the passage through which the flail travels remains within range of the player. The range requirement, as well as the player's inability to attack enemies, can be deliberately taken advantage of to increase difficulty. Note how the actuator blocks at the beginning are inactive on the top, and active on the bottom, so as to break controllable magic projectiles that attempt to gain entry.

A completely compacted version, showing only the necessary base components:

A uni-directional hoik can also be used as a more advanced one-way passage setup.

Single-use mechanisms can easily be used to create pseudo-event flags. Simply wire the initial trigger, whether it be a switch, a pressure pad, a player-above sensor, or something else entirely to the single-use mechanism, and then wire the output of that to the changes you wish to enact (e.g. Announcement Box message, actuating one or more sealed passages, etc.) A number of suitable secondary mechanisms that can be activated by this can be found in the Terrain Restructuring and Enemy Spawn Mechanics sections.

One can also 'turn on' another mechanism by wiring said mechanism to one of two logic lamps above a logic gate, and wiring the single-use target of the event flag to the other. A pair of teleporters is used in the below example. It should be noted that this setup does not include a single-use mechanism, and thus the teleporters can be turned 'off' by flipping the switch again. While the teleporters are 'on', an actuated block is made solid, preventing the spear trap from striking the pressure pad, which would otherwise cause the Announcement Box to display a message indicating that the teleporters were not working. Turning the teleporters 'on' also turns on nearby light sources, and actuates the blocks in front of the second teleporter, hence encouraging the player to pull the lever before attempting to progress. On a real map, of course, the teleporters would be placed much farther away from one another, and the mechanisms themselves would be hidden well off-screen.

Making de facto cutscenes is a relatively simple matter. Upon activating the trigger that begins the cutscene, wire all of the different effects to be used to different outputs on a delayed mechanism. For example, if one wished for several lines of dialogue to appear via Announcement Box, each box could be wired in sequence to successively delayed sections of the overall mechanism. As the nature of cutscenes here is entirely arbitrary, any number of effects, such as light sources changing configuration to make a pattern, a pathway opening up one piece at a time, a change in music via a music box, and more can be used to achieve the desired effect. Creating a de facto cutscene thus does not require any singular technique or method, aside from the ability to control the times at which certain actions occur.

It may be desirable, or even necessary to prevent the player from walking away while the cutscene mechanism is running. To these ends, actuated blocks could be turned solid to block the exit, and trap the player in the relevant area until the scene is finished. Be aware of the possibility that the player will use a teleportation item or exit the world while the mechanism is running, and plan accordingly. Ways to prevent the mechanism from breaking include putting a lever that can open up the exit passage, but only from the outside, allowing re-entry if the cutscene did not complete last time, and making it so that the single-use portions of the mechanism only become sealed once the final trigger has been activated, so that the cutscene is only barred from replaying once the entire thing has been completed. It is, of course, possible to simply cut out the single-use mechanisms, if one desires for a cutscene to play multiple times, such as during a particularly dramatic teleporter usage, for example.

The lunar pillars can be placed anywhere on the map in TEdit, just like NPCs.

An area along the vertical and horizontal edges of the map cannot be traversed in-game. Enemies can spawn in and travel through these regions freely, however. These normally inaccessible regions can be freely modified in TEdit, and mechanisms placed 'out of bounds' will function normally, though players still cannot be teleported to an invalid location.

TEdit can be used to create maps of arbitrary size, though the maximum size is still no larger than a large world. It should be noted that when using custom map sizes, strange visual effects may occur at the horizontal and/or vertical extremes of the map, as shown in the image above. If the map is especially small, world layers (i.e. space, surface, underground, cavern, Underworld) will become distorted. The size of the Underworld is largely static, thus, especially short worlds may be comprised entirely of Underworld at their most extreme. By altering the surface and cavern levels, it is also possible to make a larger map completely composed of underground/cavern areas, though this does not enlarge the Underworld.

If part of a sprite, such as a piece of furniture, is erased or overwritten in TEdit, but some parts exist that are not, the sprite will become unstable in the same vein as a candle placed in an invalid location. Actuating a nearby block will dislodge it, but if the sprite's only remaining parts are de facto invisible, this can be used to create the impression of spawning an item from nothing.

If there is a sufficient quantity of meteorite on or above the surface of a given world, additional meteors will not spawn. This can be invoked deliberately in order to prevent meteorite impacts on an adventure map by placing a large quantity of meteorite out-of-bounds in space. More information can be found here.

Advanced Hybrid Mechanisms
Now that you know how to build all of these different mechanisms, you can create more advanced, hybrid mechanisms, as well. The example yo-yo maze from earlier in this guide already showcased a basic example, wiring the end of the maze to a single-use mechanism. Speed checks/timed obstacles courses inherently required delayed, self-regulating mechanisms in order to function. The example mechanism from this guide that was created to run at first world load was combined with a delayed mechanism. Many other such straightforward combinations exist. Here, I will walk you through a much more complex example. There are a lot of moving parts here, so read and look carefully.

This setup assumes that the player possesses some form of projectile weapon, but does not require anything else. In terms of physical structure, the player can enter from the bottom-right corner, climbing the web rope and then proceeding down the stairs to the main area.

One thing to note is that all of the mechanisms' 'under the hood' parts, such as logic gates and timers, are placed within visible range for demonstration purposes. On an actual adventure map, one would want to place them off-screen, especially so that timers could not be manually tampered with, as timers can be activated directly by right-clicking them.

Starting with the wall on the center-left, this mechanism features a number of pressure pads, each of which are wired to a separate logic lamp on top of an AND logic gate. To the right, there is a purple weighted pressure plate, wired to a column of actuated blocks that are in front of the pressure pads. The player must stand on the weighted pressure plate to actuate the blocks, as they will return to their solid state once the player steps off of it. While standing on the plate, the player hits the pressure pads with projectiles until they have all been struck once. Striking one a second time will turn its respective lamp off, but striking it yet again will turn it on once more. Once all of the logic lamps are active, the logic gate activates a dart trap in the floor below the weighted pressure pad. The final output functions as a single-use mechanism, with the pressure pad struck by the dart both solidifying a block in front of the dart trap and activating a secondary 'progress' mechanism below (discussed later).

This next one is a little more complicated. The mechanism on the top-right contains five levers, each wired to a different target. As the mechanism's inner workings are completely sealed, the player cannot physically interact with them, and must rely solely on the levers to manipulate the chamber. The solution is as follows: The lever on the far left activates a spear trap and two dart traps, with blocks and pressure pads beneath them. The pressure pads below the dart blocks alternate the state of the actuated blocks when struck. In its initial state, the middle and left lanes are blocked. After firing once, only the right lane is blocked. However, regardless of state, the spear trap will not hit its mark, either due to the left lane being blocked initially, or the middle dart striking its target and closing the left lane before the spear can reach its target. Due to the fact that spear traps have a shorter cooldown time than dart traps, however, the player can spam the far left lever until the spear trap fires during the middle dart trap's cooldown time, allowing it to hit the pressure pad below, and actuating the blocks in front of the flame trap in the middle.

After this, the middle lever can be pulled to activate the flame trap. However, due to the water in the chamber on the right, the flames will not reach their target. Pulling the second lever from the right will actuate the blocks under the water and allow it to fall, giving the flame trap a clear shot, which will actuate a block on the bottom. Due to its extended firing time, however, the flame trap will activate the pressure pad twice, turning the block solid once more. There are four solutions to this problem. The first is to drop the water a moment after the flame trap begins to fire, only giving it time to hit once. The second is to drop the water, and then make the blocks in the water chamber solid again. Upon firing the flame trap, the far right lever can be used to activate the inlet pump, which will send water through the outlet pump above, and back into the chamber, blocking a second activation. The third is to leave the floor in the water chamber actuated, and simply spam the far-right lever after the flame trap activates the pressure pad, until it stops firing. This method is somewhat unreliable, though, but it only needs to work once, so it's still a viable solution. Water can also be transported back up to retry the first method, if one's original timing on actuating the blocks was off. The lava in the top-right corner of the mechanism contains wooden beams, destroying any excess water that spills over, and preventing liquid duplication from breaking the mechanism.

An alternative solution, which I did not initially consider, is to simply pull the second switch from the left immediately after activating the flame trap. The dart will strike the pressure pad before the flame trap is able to turn the bottom block solid again. It is important to properly test one's mechanisms, and look for out-of-the-box thinking, as a particularly egregious unintended solution can potentially be progression breaking. Once the dart trap on the bottom shoots the pressure pad on the bottom-right, the puzzle is complete. The puzzle itself is inherently a single-use mechanism, as the bottom-right actuated block is initially pass-through, but permanently solidifies when the final pressure pad is struck. The final pressure pad also sends a signal to the 'progress' mechanism.

The bottom-right mechanism is a bit tricky, so I'm going to take things one step at a time. Firstly, the nearby lever sends a signal to a dart trap below, which shoots a pressure pad. This pressure pad solidifies a nearby block, preventing the activation method from being spammed, but this isn't actually a single-use mechanism, as you'll see. The pressure pad also activates a one-second-timer, which is wired to some nearby blocks with actuators, as well as a number of traps inside. Recall the checkpoint and automatic traps mechanism from earlier in this guide. At the top-left of the internal trap course are two alternating walls of blocks with actuators, which toggle in tune with the one-second-timer, and thus only allow passage while the traps are active.

Note that the initial pressure pad is also wired to a nearby five-second-timer, which is itself wired to another five-second-timer, which is wired to another still. Five seconds after the traps start, the five-second-timer on the left will activate the one beside it, and five seconds after that, the middle one will deactivate the one on the left, and activate the one on the right, which will in turn deactivate the one in the center after five more seconds. A total of fifteen seconds after the traps become active, the five-second-timer on the right activates the dart trap beside it, which fires and strikes a nearby pressure pad. This pressure pad does three things: it deactivates the one-second-timer, turning off the traps and checkpoints, it turns off the five-second-timer on the right, and it actuates the block in the initial firing lane, so that the mechanism can be reactivated. If the player could spam the activation mechanism, this could potentially break the mechanism in its entirety. In the unlikely event that the player exits the world while the mechanism is running, the timers will be inactive, but the block in the initial firing lane will remain solid, preventing the mechanism from activating. A lever down below has been placed as a fail-safe, allowing the player to manually actuate the block again in the event of such an occurrence. A junction box is used there to split the blue wires into vertical and horizontal components, and prevent their interaction.

If the player reaches the end in time and steps on the pressure plate, a dart trap fires in a single-use mechanism on the bottom-left, which sends a signal to the progress mechanism. If the player does not reach the end in time, the actuated stairs against the center-left wall will allow the player to walk through the wall when moving left, granting one-way passage out of the mechanism.

With the timers set up as they are, the trap gauntlet has a time limit of fifteen seconds. The exact time limit is highly customizable, as timers can simply be laid out in a line, each wired to the one next to it, and they will generally behave well. When counting time, start by reducing your desired time limit to the highest number divisible by five. Let's say you wanted a time limit of 24.4 seconds. This would round down to twenty, which when divided by five is four, meaning that you would place four five-second-timers in sequence for the first twenty seconds. If you have at least three seconds remaining until your desired time, then place a three-second-timer after that. If you have at least one second remaining after both of those steps, place one-second timers until you do not. In this case, the timer configuration would be 5-5-5-5-3-1. Lastly, if you wish to add time of less than one second, hook the one-second-timer to a dart trap, with a firing lane of the desired length, and a pressure pad at the end. Recall that darts travel at 45 blocks per second, with half speed in water, and one quarter speed in honey. So if you wanted to add 0.4 seconds, the lane (starting from the second block in front of the dart trap) would be 45 * 0.4 = 18 blocks in length. If you do not wish to add extra time, simply put one block directly in front of the dart trap, and then put the pressure pad directly in front of that. Wire the pressure pad to your final timer to deactivate it, and turn off the mechanism. Note that each successive timer will function properly if its time is equal to or less than the timer before it. If it is greater (such as a 5-3-5 sequence), then the faster timer will repeatedly toggle the slower one, which will be unable to turn off the faster timer as a result, stopping the timer cascade dead in its tracks.

Lastly, we have the progress mechanism itself in the bottom-left corner. Each time one of the other mechanisms is completed, the progress mechanism receives a signal, activating all three dart traps inside. This functions, at its most basic level, as a simple finite-use mechanism, each lane barred from hitting its target due to solid blocks, actuated by pressure pad in the lane above, and solidified again by the pressure pad in the lane below it. Each of these three pressure pads is also wired to an announcement box, which gives off a message indicating the completion of the mechanism (1/3, 2/3, and 3/3 complete). These messages correctly tell how many have been completed regardless of order, due to the fact that all mechanisms' 'progress signals' fire all dart traps. For this reason, however, the mechanism does not know which of the other three was completed. Because the mechanisms that send the 'progress signals' are all single-use, there is no risk of one mechanism registering as completed multiple times. Each of the aforementioned 'progress signals' also actuates one row of blocks barring passage through the bottom-center. In this case, each row that actuates is tied to a specific mechanism, and so their order of actuation depends on the order in which the mechanisms are completed. If they were instead wired to the progress mechanism in the same way as the announcement boxes, they could be forced to actuate in a specific order, regardless of which mechanisms were completed when. Also, if the progress mechanism, or the individual 'progress signals' targeted logic lamps over an AND logic gate, they could be made to open the entire passage at once, but only once all three mechanisms were completed.

The progress mechanism can be scaled up or down depending on your needs, and outfitted with any number of secondary effects upon activating a certain number of mechanisms. An especially robust progress mechanism could even be used for an entire map, allowing the player to complete an arbitrary number of disparate tasks in any order in order to progress.

Note that blue and yellow wires intersect one of the chandeliers inside the progress mechanism. Normally, one would not put light sources inside something that isn't supposed to be visible, but let this simply serve as a reminder to be careful where one is placing wires, so as to avoid unintentionally toggling something. Be aware that in addition to lights and obvious mechanism items, doors can also be toggled via wiring. Another word of warning is to watch for the length of the player's reach. In this example, the player can open the treasure chests below while standing on top of the bottom barrier, making completion of the bottom-right mechanism unnecessary. A player's reach can also activate levers or switches from places where this may be undesirable, so be sure to place such things in well-considered locations. Alternatively, a player's reach can be invoked, rather than suppressed, by placing a lever or chest in a place the player cannot physically get to (such as inside a wall), but a short enough distance away that they can still right-click it.

Extras - The Request Box
Any mechanisms added to the guide by reader request will be placed here.

Final Notes
One final piece of advice: playtest, playtest, playtest! The only way to be sure that your map works is to actually see it for yourself. Make a copy of the world file (My Documents -> My Games -> Terraria -> Worlds, at least that's where it was saved by default for me), and then playtest it thoroughly. Even in the process of making the video to go along with this guide, I found that some of the mechanisms I had built did not work how I had originally intended, and I even learned a few things in the process of fixing them (which were retroactively added to the previous sections of this guide prior to release).

Aaaaaand... that's pretty much it. Now, it is obviously true that there exist other mechanistic setups in Terraria, but to cover literally all of them is beyond me, and would balloon this guide to absurd lengths. The promised supplementary video can be found below, in which all of the major mechanisms from this guide (including a slightly modified advanced hybrid mechanism) are shown in action.

As always, if you have any questions or comments, leave them in the comment section below, and I'll answer your questions as soon as I see them. Also, if you have any requests for types of mechanisms or techniques that I didn't originally include, but you'd like to see me cover here, you can leave those in the comments as well, and I'll consider adding them to the guide. Remember that this guide is geared towards adventure map creation, so mechanisms that have a purely practical use, and thus don't have a place on an adventure map (such as enemy or item farms), will not be added.

VIDEO SUPPLEMENT: