Afgrond

History
The great abyss, a prison for beings of great power. The prisons seal can only be broken by the touch of the great being who himself sealed the cage. Used to hold Diabolus during the Age of the Makuta. Has only ever been opened two times, once by Akimu, and the other by Imperio.

Features
The entrance to the chamber of Afgrond is invisible to all but any who are wearing the Kanohi Meztok, the Mask of Enhanced Mimicry, mask of Imperio. The chamber is a massive vault with a domed roof, and six thick ebony columns surrounding a trapdoor on the floor, beneath which is the prison.

Trivia
-Afgrond has no astronomical position, it literally does not exist in your personal reality until you wear the Meztok.

-The ebony columns are actually the six keys that open the trapdoor to release the prisoner.