This arena is used for defeating the Eater Of Worlds and the Eye Of Cthulhu, I would recommend using a ranged projectile weapon, or magic weapon from the dungeon. (water spell, or aqua scepter.) I would also recommend having mana potions and a high amount of maxed mana. You defeat him by moving up and down on the platforms while firing you magic or melle weapon at him at ALL times! If you stop, he might dig under you, do not stop moving!

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