The Eater of Worlds has fifty body segments, and each segment counts as an enemy. Since it's easy to beat, this boss is great for binge battles.

To spawn the Eater of Worlds, destroy three Shadow Orbs with any Hammer or make Worm Food with fifty Vile Powder and fifteen Rotten Chunks.
The Eater of Worlds will (hopefully) get you the Corrupt Key.
 The Brain spawns large groups of enemies known as Creepers (that aren't green), which can drop the Crimson Key.

The Brain can be summoned two ways: by the destruction of three Crimson Hearts, or via a Bloody Spine.
On the Computer Version, make the Spine out of fifteen Vertebrae and thirty Vicious Powder.
In the Mobile Version, just use fifteen Vertebrae.


In the Computer Version, combine the Key and five Souls of Fright, Sight, and Might.
In the Mobile Version, combine the Temple Key, Mold, and Souls.
,
Spawn the Eater of Worlds.
Spawn the Brain of Cthulhu.
Make your Keys.Head down to the Dungeon.Open the Biome Chests and behold the wondrous Sight!
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