Kharos

Kharos is the smallest, southeast island of the Forbidden Islands. Many avoid even going near the island, as it is the pinnacle of evil. The evil warlock Ferumbras constructed a tower upon this island, as a citadel. When he was defeated, the mighty sorcerers of the Edron magic guild sealed the entrance to the tower with energy which was impassable unless by them. Be wary when the seals here glow bright, for the towers creator might be making his return!
See also: Ferumbras Citadel