Gul'dan by Zefn

Gul'dan was a former orc shaman from Draenor who became the first orcish warlock as well as the de facto founder of the Orcish Horde. Abandoning the ways of shamanism and betraying both his people and his mentor to the demonlord Kil'jaeden for personal gain and power, Gul'dan was directly responsible for the orcs' fall to demonic enslavement as well as for the Horde's invasion of Azeroth. Tutored by the lord of the Burning Legion, he became the founder and master of the Shadow Council as well as the original creator of the necromantic terrors known as death knights. He often referred to himself as "Darkness Incarnate" and "The Destroyer of Dreams." Gul'dan is considered one of the most powerful warlocks to have ever existed.