Mondain

Mondain is the main villain of Ultima I (and also of Akalabeth).

Mondain was the second son of the wizard Wolfgang. He murdered his father and stole the his gem of power, which would later be turned into the Black Ruby by Mondain. Because of his rage and immaturity, Mondain caused horrible suffering and sorrow for the people of the land. Mondain was destroyed by the Stranger by means of decapitation. Mondain's head was taken (probably by his apprentice Minax) after the battle.

It was later reconstructed that Mondain attacks Sosaria for a first time in Akalabeth, but the player's efforts in that game deflect his attack, making him frustrated and finally leading to the events of Ultima I.