Darcalus

Darcalus was the undead aspect of the lich-king Azalin, separated from Azalin's human half when the Dark Powers gave Azalin a "second chance." Darcalus had no memories of his mortal life, and seemed to be a crueler individual than the complete Azalin. The domain of Darkon was formed around Darcalus, and remained his until Firan Zal'honan, the human half, invaded Castle Avernus and destoyed Darcalus' phylactery. As the pair met one another, they recombined as Azalin once more.

Darcalus had two other notable differences from Azalin himself. First, when he pretended to be a mortal, he wore a form similar to that of his deceased brother Irik Zal'honan. Second, he could use the power-magnifying room of Castle Avernus without feeling any pain, because he had no living form to regenerate into.