Player-made Structures

Boss Arena
A boss arena is a battlefield designed to give players an extra edge when fighting against bosses like the Eye of Cthulhu or the Eater of Worlds. While boss arenas do vary depending on the boss being fought and the player's tastes, they typically have the following features: For example, say that a player wants to fight against the Eater of Worlds in an arena of their own, they might decide to build a long arena out of dirt with corrupted grass or Ebonstone, and they might also wish to build 1 or 2 long rows of wooden platforms in case the Eater of Worlds tries to attack by sliding across the surface of the ground. The arena may furthermore be enclosed with walls and a ceiling so that outside enemies won't interfere, and so that ammo from various ranged weapons, such as shurikens or wooden arrows can be retrieved and reused during the battle against the Eater of Worlds.
 * Lots of open space to move around and use ranged weapons in.Eater_of_Worlds_Arena.jpeg
 * 1 or more rows of wooden platforms: Mobility in all directions (including up and down) is often a key factor in surviving boss battles in Terraria. Unfortunately, since not everyone has, say, Rocket Boots or a Cloud in a Bottle at their disposal, building 1 or more rows of wooden platforms should grant even a new player the ability to move in any direction more freely.
 * Walls and a ceiling: Many players may wish to fight these bosses without having to worry about interference from normal monsters like, say, Zombies or Eaters of Souls. Sealing the arena off from the outside with walls and a ceiling should do the trick, allowing players to focus more of their attention on the bosses themselves. Players that use ranged weapons that can be reused, like a bow and arrow, or shurikens, could also find walls and a ceiling useful for making it easier to retrieve said projectiles and reuse them during the boss battle.
 * Corrupted grass and Ebonstone (only for arenas that are designed for fighting the Eater of Worlds): As of patch 1.0.5, the Eater of Worlds can only be fought in The Corruption, and at least 500 blocks of corrupted grass and Ebonstone combined are needed within close proximity of the arena in order for the game to determine that it lies within a valid corrupted area.

Caisson
A Caisson is a structure that allows characters to create shafts through water and empty space. It is simple to construct: simply place a row of blocks 4 wide and 2 deep, underneath the character then mine out the center 2 blocks and repeat. If you wish to capture some water for the shaft you are creating, create a U shape out of blocks first and then continue normally.

This method can be effective for lower level players who wish to descend corrupt chasms without other means of traversal / navigation e.g. the grappling hook, featherfall potion or orb of light. However, players should be warned that Dynamite or purification powder is essential for breaking through the ebonstone (short of a nightmare pickaxe) that protects shadow orbs.

Additionally, use of this method horizontally along the surface of the Corruption can be a safer, yet slower, way to reach the entrances to said chasms.

Defensive structures
Main Article: House Defense

Simple Wall
The simplest defensive structure in the game. It is a structure composed of several blocks of material (wood blocks or stone blocks, mud blocks work too) stacked on top of each other. Beginners might find this structure very useful, as it is incredibly simple to build, yet very effective at keeping monsters at bay, when not in Hardmode. Occasionally, players can build doors in the walls, to be able to walk through the walls, while keeping most of the enemies at bay. The principal advantages of the wall are:

- It is very easy to build and it needs only common materials

- You can use them as cheap protection methods while you don't have a house yet

- You can use them for escape points, as you can run through the open doors, then close the doors on the monsters

- Very useful when night comes and you are far from home, just go to the nearest wall and build another one, and you will prevent zombie agression while being able to easily defeat demon eyes and loot their drops

It is NOT reccomended to use them during blood moons, as zombies can open doors.

Floating Base
Building your house in the air prevents any sort of land monster to enter your house regardless of their ability to knock down doors. Flying creatures can still be a problem but are easily nullified with platform traps and doors. Building a house like this is completely impregnable except by Goblin Sorceror, Worms or Bosses. As seen in the screenshot on the right, only one Zombie is allowed to spawn despite Blood Moon due to how many Demon Eyes are trapped, in addition the player can fight on the ground with melee or from the central "Airlock" of the house with ranged weapons. The only issue with this type of house is it can be detrimental to one's sense of reality.

Sand Shell Method
An effective Blood Moon/Goblin Night defense system includes sand on top of a torch or a door, where the player breaks the torch or closes the door and sand falls on the entire home, blocking off all entrances. A major drawback is that it is very tedious to clean up. You can make the sand as tall as necessary depending on how many entrances you have. However, setting up the system is comparatively tedious. As of 1.1.1, you can now also place sand on active stone blocks, and using wiring and a switch, trigger the stone block to be active therefore dropping the sand onto any monsters.

Tower Method of Self Defense
Utilizing a similiar method to the floating base however it is connected to the ground when it is locked down using two sand traps to block the bottom of the tower. The tower uses two platform traps to allow harvesting of Demon Eyes. The traps can be made into any prefered size. The advanced versions of the tower can use a secondary sand blocking system.

Dart Trap Fortress
If you can get your hands on enough Dart Traps, wires, and pressure plates, then you can design a dart trap defense as shown below, simply put, when this many dart traps are wired up, you can effectively fight blood moons, goblin armies, and frost legions from the comfort of your throne.



Farming
Farming is a new addition, as of 1.0.5. The player uses seeds obtained from flowers to make more and more flowers, in a way that it is close to home and easy. Certain farms will have certain things, such as hatches to allow water/lava in (for Fireblossom or Waterleaf) or chests that hold everything they may need, like buckets and seeds. Farming allows potions to be made much easier, because you will have the plant ingredients growing, and if you grow them right, you can get seeds out of them.

Hellevator
Main Article: Hellevator

'Hellevator', also known as 'Hellvator', is the Terraria jargon for a drop from the main land to The Underworld (Hell). It is a portmanteau of Hell and elevator, for obvious reasons. Usually at the bottom of a Hellevator is Water, since it removes fall damage, but you can also use Cobwebs, Dual Hooks, Grappling Hooks, Ivy Whips, a Lucky Horseshoe, Demon Wings, Angel Wings, a Cloud in a Bottle, Spectre Boots or Rocket Boots.

House
Main Article: Home

A home is a safe haven for players or NPCs where they can spend their Nights without fear of attack under most conditions. If Blood Moon has risen, during which Zombies can open doors, or a Goblin Invasion has begun, in which goblins can open doors, the home is no longer a guaranteed safe zone. Unless you block the doors with bricks. The only mob that you must worry about then, is the Goblin Sorcerer. The home can take very various forms, ranging from a simple shack to an elaborate mansion or even, the famous World House. Usually, the first home is a room with wooden walls, a crafting station, one or two doors, one or two light sources (usually torches), and background wood walls. After that, you can take one of the many develloping paths:

- Building outposts near important landmarks or to have safe places to rest

- Building a linked Hellevator or simple mining shaft

- Link different spots of the map

- Or simply develop your main house into a giant castle

- Build a Skybridge, linked or not

Liquid Generator
Main Article: Generator

A liquid generator is a structure that is used to create more water than is used in the process. Liquid Generators are useful if one wishes to flood large parts of the world (most notably, flooding the Underworld with water), and they are typically used for building Obsidian Generators, which are designed to create infinite amounts of Obsidian.

Skybridge
Main Article: Skybridge

A skybridge is a player-made level surface, built at a reasonably high altitude, that spans part or all of the world's horizontal length. This is primarily used to: collect Fallen Stars (as they will fall on the bridge and can be collected by running across the Skybridge), find Floating Islands, and grant an easy route to other parts of the map (Dungeon, Underground Jungle etc). The main con about this structure is that if Meteors fall on it they will grant very little Meteorite Ore. However, if the skybridge is high enough (about 10 blocks below the top map limit), Meteorites may land in the ground, but fallen stars will stlll land on the skybridge. This is maybe because Meteorites start falling under that level and skip the skybridge, but fallen stars start falling from the top of the map.

Traps
Main Article: Traps

There are many kinds of traps that players can create with a variety of functions, both for dealing with monsters and for PvP. These include wooden platform traps, which can trap flying enemies; lava traps, which can be used for automated farming of enemy drops; and pitfall traps, which are used in PvP matches to drop an unsuspecting intruder into something deadly like lava.

Wire Creations
Main Article: Wire Creations

Patch 1.1 introduced a new wiring mechanic that allows players to create mechanical devices, including pressure-plate-activated dart traps, drawbridges, switch-activated secret doors, and crab-powered engines to name a few.