The Actuator is a device that allows any solid block to be toggled on and off much like Active Stone Blocks. Actuators are placed much like wire; they can be placed over blocks or in empty space with or without walls. Once placed, they act like wire in that they disappear when not holding a wire item and can only be broken with a wire cutter (breaking the block they are on will not remove the actuator).
Actuators can be used for the easy collection of (Glowing) Mushroom farms by placing them on every block where a mushroom grows. This principle can likely be applied to other items that grow on certain blocks such as crystal shards and fireblossoms. They can also be used to hide secret bases, as well as various other uses.
Actuators can be used to replicate an effect of doors; much like when doors are opened, when blocks become inactive, players grappled to the block fly forward at high speeds. This can be used to reach maximum speeds nearly instantly. When combined with pressure plates, this effect can be triggered automatically.
- When placed on a Dirt Block and turned inactive, the block is turned into a Clay Block until the player reactivates it.
- Actuating a block under most Furniture will make it pop off and drop as an item.
- Actuators only work on blocks and traps and surprisingly, Platforms and Teleporters.
- Using Actuators on blocks under Trees, Demon Altars, Crimson Altars, or any Chests (even if its empty) doesn't work.
- De-activating blocks under plants will destroy them as if they were struck by a tool. This can be useful for constructing mushroom farms. Herbs are apparently unaffected and will remain in place.
- Liquids will pass through inactive blocks, but falling blocks like sand, silt and slush will still be supported by the inactive blocks.
- De-activating Hellstone in The Underworld will allow you to pass through it without generating lava, it also works for hive blocks preventing it from spawning bees or generating honey.
- Inactive Ebonstone, Crimstone, and Pearlstone Blocks will not prevent them from being considered to form their respective biomes.
- Naturally occurring Lihzahrd Bricks cannot be actuated until Plantera has been defeated.
- Standing within inactive blocks and then re-activating them will allow you to move about 6 blocks but will not allow further movement. This may be handy as a protective hiding spot.
- Actuators work on Locked Jungle Temple doors in the console edition.
- NPCs can spawn on top of inactive blocks and fall through them.
- Inactive blocks created by actuators in the walls of NPC houses will cause the housing to become unsuitable. While the NPC will remain, if a world is closed while the housing is unsuitable, they will move to any available other house.
- Placing an actuator on active wire will not activate the actuator, it will reverse the actuator's mechanics: that is, when the wire is off, the block will be inactive when it would normally be active. This makes it possible to use one trigger to change one block to a solid state and another to a non solid state. This can be used for example to make a drawbridge of sorts, one set of blocks covers a lava trap and another section blocks access to your base (see pictures below).
- Deactivated blocks do not show up on the minimap.
- If a block is deactivated and mined, any block placed there will remain deactivated until its state is changed once again with an actuator.
- Added to the game.