AD&D Greyhawk Homebrew
Thargus the Arch-Mage originated in the first campaign
Thargus assembled the original party members to seek out objects of power created by the Ancient Flan to defeat the evil that his superior divined would consume all of the Oerth.
He guided them, came to their aid and at some point captured by the minions of. The party never found out what happend to their benefactor.