In Ultima I, Mondain the Wizard placed his stronghold in the Time of Legends, rendering it inaccessible. It was there, where he stored his Gem of Immortality, so that his reign of terror would be endless. Thankfully, the Stranger managed to acquire a Time Machine to travel back in time and reach the fortress, slaying the foul Mondain by shattering the Gem of Immortality and ending his reign of terror.