From the Soulcalibur Wiki
Kunpaetku is High Priest of the
Fygul Cestemus sect and is the one who created
Astaroth at the God of War's request. He, however, wanted
Soul Edge to himself, so he can turn into a god. Unfortunately for him, Ares' agent of death, Ker, dwelled inside the monster and Kunpaetku lost control over him. Trying to use a curse to control him again, he only obtained Astaroth's rage and the destruction of his shrine, the Shrine of Kunpaetku. He survived only to find
Maxi, who killed him shortly after.
Kunpaetku from SC1 ending