Jaqon

Jaqon is an exiled devil who lives on Avernus, the first hell. Asmodeus exiled Jaqon for a great betrayal. He changed Jaqon's name to Dagon to so that if someone tried to summon him, instead they would summon the powerful demon lord's aspect.

Jaquon led his followers in a battle against Asmodeus to become an archdevil.