This is the game's "secret" boss. It is the Demon King that you prevented from being completely revived in Path B of the Forgotten Sanctuary. You fight him at full power on floor 9-1 of the Labyrinth of Chaos. Within the game's story, he is responsible for giving the Dragon's Crown the power to control dragons in exchange for Wallace's soul until the player recovers the stone tablet contract and gives it back to Wallace, who destroys it. The Demon King's real name is Majino-Gusna-Idra-Shin.
Abilities & Attacks
Dragon's Crown (Video Game)
Dragon's Crown (Manga)
The Demon King's name for the boss battle is actually DemonLord.
The Demon King has the same musical theme that the Ancient Dragon has. He also appears to be stronger than it.
The Demon King's vocals in the game's English version are the same vocals in the Japanese version.