Black hole (A Soul's Bane)

The Black hole is encountered during the A Soul's Bane quest, in the room of fear. If trying to enter it, at first your character will refuse, saying: "This door's darker than the rest. There's no WAY I'm going in there!"

However, after you have defeated five fear reapers, the black hole will fill with light. This allows players to enter it, and thus teleport to the next room, the room of confusion.