Mecha Rogue X

From Wikimon

Mecha Rogue X is the final boss of Digimon World X who you will fight throughout the game. At the beginning of the game he is known simply as Mecha Rogue. He takes control of Leomon, damaging his mind. At the final battle on Machine Pit Mecha Rogue X has three forms:

Mecha Rogue X (Form 1) Mecha Rogue X (Form 2) Mecha Rogue X (Form 3)