Magnus was one of the Untainted living at the Mountain of Fire in 164 of the Fifth age. He was the resident healer.
When Arisha came to the Mountain of Fire ill, Magnus cared for her. He was also part of the group that subsequently went and hunted her down for stealing rune essence. When the Kinshra, Varrockian guard, Arisha, Castimir and Kuhn were trapped in the Labyrinth, he came twice offering to spare them in exchange for Arisha. When she gave herself up, he cured her of the poison infecting her.