The Black Fortress is the most powerful prison. Before the Emperor summoned it to the Caribbean the Fortress was appart of the World Tree Yggdrasil in the Norse Myths. The Black Fortress is a prison no one escapes (eccept for The Brothers of Chaos). In the Fortress you face your worst fear, your fear is your guard.
The Black Fortress NowEdit
The Black Fortress is now inside the Island of Devils Anvil.