I'm not much of a mechanic in Terraria, but here are some ideas:
Elevator Rails
These rails can be placed on walls, and will carry platforms made of blocks, which are connected together through "elevator connectors"*. Activating the rail through wire will cause the platform to move forwards, until reaching the end, and will stop. If activated again, they will move in the opposite direction until reaching the end, and so on and so forth.
Putting an elevator rail in a loop will cause the platform to move in a loop endlessly, granted that a constant connection is maintained. Should the connection be stopped, the platform will stopped where it is.
*alternative idea: Instead of connected blocks, these platforms only use special "elevator blocks" or rideable lifts that have a set width.
Wire Cutoff
A block that allows wire to pass through it from left to right. It maintains the state of the wire unless activated by another wire from above.
Button
Like a switch, but only activates wires for a second or so.
Conveyor Belts
Will move both mobs and items, depending on the direction the belts are facing. Activated by wire.
Vaccum & Tubes
Tubes can be placed like wires, and they connect to chests. When activated by a wire, the tube will take items out of one chest, and place them into another. The direction that the tubes move items can be changed. If a tube is not connected on one end, it will not work. (Alternatively, it will dump the item out on the floor!)
Vaccums can be connected to tubes, and when activated draw in all items within a 3-block radius. When collected, they send items to the chest they are connected to.
Turret
Turrets can be used to defend a base, but they have limited health. Should the break, the player will need to re-activate them, which will take about 5-10 seconds, without getting interrupted. They also fail to function during boss fights, meaning that you cannot simply just "buy" your way to victory.
A few Turret types:
- Dynasty Turret - Fires wooden arrows can only fire directly left or directly right.
Deals 5 damage, and has 50 HP.
Made using 100 Dynasty wood 20 Silk and 50 Clay Blocks.
- Iron/Lead Turret - Fires Bullets, and can only fire directly left or directly right.
Deals 10 damage, and has 100 HP and 5 defense.
Made using 50 Iron or Lead bars, and 20 wire.
- Hallowed Turret - Fires arrows, and can fire in all directions.
Deals 27 Damage, and has 200 HP and 15 Defense.
Made from 20 Hallowed bars, 20 wire and Illegal Gun Parts.
- Security Turret - Fires rapid bullets, can fire in all directions, and must be placed on the ceiling.
Deals 10 damage per bullet, and has 100 HP with 10 defense.
Made using 20 Shroomite bars, 20 wire and a black lens.
Statue Activations
Activating certain statues will cause the surrounding environment to change, similar to the monoliths.
- Activating a Gloom Statue will cause the surrounding environment to become gloomy and foggy, as well as make the surroundings darker.
- Activating a Tree Statue will cause the surrounding environment to gain a greenish tint, as well as gain particle effects that resemble fireflies and leaves.
- Activating a Corrupt Statue will cause the surrounding environment to gain a purplish tint, as well as become hazy.
- Activating an Imp Statue will cause the surrounding environment to gain a reddish-orangish tint, as well as become smoky. It also gains particle effects that resemble embers.
- Activating a Reaper Statue will cause the surrounding environment to become cloudy, and have the occasional lightning strike in the background.
- Activating a Sunflower Statue will cause the surrounding environment to become sunnier and brighter.
- Activating an Anvil Statue will cause the surrounding environment to gain a slight sepia-tan tint, as well gain dust clouds.
Activating other statues cause other effects.
- Activating a pot statue creates an empty pot somewhere within a 100 block radius.
- Activating a potion statue clears the potion effects of anyone standing within a 5 block radius.
- Activating an eyeball statue will spawn a demon eye. It drops no items other than cash.
- Activating a hornet statue spawns a hornet. It drops no items other than cash.
- Activating a goblin statue spawns a goblin. It drops no items other than cash.
- Activating a cross statue will cause a ghost to spawn. It drops no items other than cash.
- Activating a gargoyle statue will cause all players within a 5 block radius to have the "Stoned" effect placed on them. Will only be activated every 20 seconds.
- Activating the woman statue temporarily changes the gender of anyone standing within a 5 block radius, for 10 seconds.
- Activating an angel statue does nothing, because that would kill the joke.
Pillar Fountains
By combining "Pure Water Fountains" with respective fragments, you are able to create either a Vortex Fountain, a Nebula Fountain, a Solar Fountain or a Stardust Fountain.
All of the water changed by these fountains glows in the pillar's respective color.
Pillar Lamps
Light sources for each of the pillars.
Large Doors & Gates
Simply doors that are larger than their counterparts. They may or may not take more time to open.
Locked doors
Doors that can only be opened and shut depending on the condition they're set to.
Either:
- Anyone can open them.
- Only the person with the correct name can open them.
Biome Protector
Creates a 20 block area that when activated, does not allow for biome spread of any kind, whether it's Corruption, Crimson or Hallow.