The castle was first seen in Ultima III, when it served as the nearly impenetrable island fortress of Exodus. The Isle of Fire was reachable by a moongate. However, the castle itself could only be reached by ship. The party had to fight their way through, to find and destroy the twisted offspring of Mondain and Minax. After that, it was repaired by Lord British as a test for the Quest of the Avatar, but the island sank before Ultima IV.