When Cadderly Bonaduce wanted to destroy the evil magical sentient item Ghearufu in 1362, a divine inspiration from Deneir informed him that he needed the fire of a dragon. Cadderly went to Fyrentennimarr's lair. At first, Fyrentennimarr didn't want to help. As last resort, Cadderly used a powerful spell to change the dragon's alignment, and the dragon, now a gentle creature, collaborated to destroy the evil Ghearufu.
Later, with this powerful ally, but only until the end of the spell, Cadderly decided with his party to assault and destroy Castle Trinity. However, the magic defenses of the castle and the end of Cadderly's spell confused the dragon and in the end Fyrentennimarr was killed.