Dungeon Guardian

The Dungeon Guardian is an enemy in the indie video game Terraria. It is the most powerful creature in the game and it was originally intended to be undefeatable.

Appearence
The Dungeon Guardian is a giant floating skull, identical to that of Skeletron.

Behavior
The Dungeon Guardian is used as a way to prevent the player from accesing the Dungeon when Skeletron hasn't been defeated. Up to 15 of them will spawn if the players enters the Dungeon before killing Skeletron and they will kill them.

Dungeon Guardians attack by flying into the player at high speeds while spinning.

Abilities
Dungeon Guardians have a defense of 9999, making all weapons nearly useless against them.

They also deal 9999 damage, killing the player in 1-2 hits, no matter their defense.

Loot
If a player manages to kill a Dungeon Guardian, it will drop a Bone Key.

Bestiary
The bestiary entry for the Dungeon Guardian says: "A lethal sentry that stands watch over the Dungeon's gates. Those who are deemed unworthy to enter shall not pass!"

Instead of being unlocked by killing the Dungeon Guardian itself, it's entry is unlocked by killing Skeletron.