ウルティマオンライン
Shattering the Gem of Immortality forms the basis of two later games, ' and "Ultima Online". Three shards of the gem are found at the location of the sunken remnants of Terfin in ', along with Mondain's skull. The shards later form the Shadowlords in "Ultima V" and are necessary to defeat them; the skull in "Ultima IV" kills all creatures within an area, also hurting the Avatar's karma. In "Ultima Online", many different shards exist, all of which are parallel universes containing Britannia.