Dungeon

The  is an enormous structure found close to the edge of the world opposite of the Jungle, spanning many layers deep, usually all the way to The Underworld. It always spawns on the right side of the world. At world creation, the Dungeon is randomly formed from one of three Dungeon Bricks and walls (Can come in blue, green, or pink variants). It is the home of the third boss, Skeletron, who will only spawn at night when talking to the Old Man but if attempted to enter before defeating Skeletron the player will face the Dungeon Guardian. Since the dungeon guardian can kill the player in one hit, and is extremely fast, it is highly recommended that one does not enter the dungeon before defeating Skeletron. Upon gaining access, the Clothier NPC will be freed and the player can then roam about fighting deadly enemies, dodge numerous traps, and discover powerful loot.



Design
The dungeon is made up of Dungeon Brick. It requires Nightmare Pickaxe/Deathbringer Pickaxe or higher to mine and is immune to explosives. The dungeon zig-zags down from the entrance to a larger, labyrinth like section where the majority of the loot can be found. The winding nature works to make monster spawns unpredictable, creating many "ambushes" from above. It is highly recommended that every character have a Magic Mirror for quick escape, as getting out is often more difficult than getting in as a result of needing to go up.

There are many rooms branching from the labyrinth where a great deal of loot can be found and can be a good resting place as monsters only have one access point to the character.

Spikes line much of the dungeon making simple traversing dangerous. They can be mined, but are harder than the dungeon brick. Placing blocks or platforms over them is recommended.

NPCs
Only one NPC can be found anywhere within the dungeon, and will be bound until the player right-clicks on them and untie them, and that is the Mechanic. However, since the Goblin Tinkerer and the Wizard can be found anywhere underground once their requirements are fulfilled, they may also spawn in the dungeon, and can be unbound the same way.

Monsters
The dungeon has a large number of unique monsters. The monster spawn may be abnormally high as there are Water Candles spread throughout, so try to break them while traversing the dungeon to keep the rate down.

Boss Monster
To gain access to the Dungeon, Skeletron must first be defeated. Skeletron is the guardian boss summoned by talking to the Old Man standing outside the Dungeon entrance at night. During the day, he will say to wait until night to talk to him. Entering the Dungeon below 0 Depth without first defeating Skeletron will cause the Dungeon Guardian to spawn, which can kill a player on contact.

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Pre-Hardmode Monsters

 * Angry Bones
 * Cursed Skull
 * Dark Caster
 * Dungeon Slime
 * Blazing Wheel (Immortal)
 * Spike Ball (Immortal)
 * Dragon Skull(Console/Mobile only)

Hardmode Monsters
Note: Hardmode Dungeon Monsters do not spawn until Plantera has been defeated.

Brick Wall

 * Blue Armored Bones
 * Necromancer
 * Skeleton Commando
 * Paladin (Miniboss)

Slab Wall

 * Rusty Armored Bones
 * Ragged Caster
 * Skeleton Sniper
 * Giant Cursed Skull

Tiled Wall

 * Hell Armored Bones
 * Diabolist
 * Tactical Skeleton
 * Giant Cursed Skull

All Walls

 * Dungeon Spirit
 * Bone Lee
 * }

Loot
The Dungeon is filled with chests containing rare and powerful tools and weapons as well as unique decorative items. Loot in the dungeon can be found laying around, as drops from monsters, or in chests. All Gold Chests found in the Dungeon are locked and require a Golden Key to unlock them. There are also 5 Hardmode Chests, described below.

Gold Chests may contain, along with normal chest loot:
 * Aqua Scepter
 * Blue Moon
 * Cobalt Shield
 * Golden Key
 * Handgun
 * Magic Mirror
 * Magic Missile
 * Muramasa
 * Shadow Key
 * Bone Welder

Other loot from the dungeon includes the Water Bolt spell, which can be obtained by smashing books in the dungeon. Dungeons are also a free source of wire and many wiring items. There are also many decorative furniture items, including paintings, beds, chairs, and workbenches, that can be found throughout the dungeon.

Hardmode Loot
Once Hardmode has been activated and Plantera has been defeated, the Dungeon becomes much more difficult. New types of enemies will spawn. When these new enemies are killed there is a chance to spawn a Dungeon Spirit, which will drop Ectoplasm used to craft Spectre items. These new enemies can be farmed for their loots and Ectoplasm. Here is a video to help explain how to farm the mobs.

Along with new enemies, the five special locked chests will become accessible (the keys to these chests will only drop in Hardmode). They each require a matching key. These keys can be obtained by killing enemies in the corresponding Biomes to get the Key Molds, and then craft with various items (the enemies do not have to be native to that biome). The drop rate is 0.04% or 1 in 2500, making them very rare. Either the Corruption or Crimson chest will not be unlockable, depending on if that world is infected with The Corruption or The Crimson, unless the player goes to a world that has the other infection.