Zelgadis is a descendant of Rezo the Red Priest, the blind sorcerer known for doing good deeds - Rezo's or your grandfather or great-grandfather. In his youth Zelgadis sought to become the most powerful being in the world, in order to "help" him, ask him turned into a chimera: part human, part golem (rock monster), and part brau demon (similar to a black elf / drow demon).