Marquis de Léon
The Marquis de Léon originally uses Balzack as a subordinate, but after gaining further power and no longer needs his help. According to The Unknown Legend, he is the prince of the castle King Leo, who used the Secret of Evolution to assume this form, and the remake depicts him accordingly: When the monster is defeated in the remake, he returns to human form, and forgets his memories as a monster.
He must be fought twice, once each in the fourth and fifth chapters. It is supposed to impossible to defeat him in the fourth chapter; if he is defeated, the PlayStation version will carry on as though the party lost, and the FC/NES version will repeat the battle. He moves twice per round, attacking, casting Sizzle and breathing frost.