|Human Partner||Akiyama Ryo|
Millenniumon is the main villain in WonderSwan game storyline (Digimon Adventure: Anode Tamer & Cathode Tamer, Digimon Adventure 02: Tag Tamers & D1 Tamers and Digimon Tamers: Brave Tamer). In Brave Tamer it is revealed that he is a temporal paradox, revealing that he was Ryo's original partner, the Dark Masters' Mugendramon who Jogressed with a Chimairamon, becoming Millenniumon, and soon after, Zeed Millenniumon, who is the mastermind behind the event of Digimon Adventure that he gave originate Apocalymon (which gave rise to the Dark Masters' Mugendramon), Diablomon and consequently, Mephismon and Meicoomon (through Apocalymon).
Millenniumon was also responsible for the creation of Digimon Kaiser, a dark personality of Ichijouji Ken controlled by a Dark Seed that was originally intended to reach Ryo. Controlled by the Dark Seed, the Digimon Kaiser created Chimairamon in an attempt to revive Millenniumon, as the original (Ryo's partner) eventually merged with Monodramon at the end of the last game before Ryo was sent to Digimon Tamers universe.
|Ultimate||Mugendramon (with Chimairamon) |
The Dark Master Mugendramon Jogressed with a Chimairamon to become Millenniumon, who then kidnapped the Chosen Children and warped space and time, reviving their old foes and causing the events of the game to happen.
Millenniumon serves as the final boss of the game, fought after defeating all the previous bosses (Devimon, Etemon, Vamdemon and Piemon) as well as one of the Digimon that formed him (Chimairamon in Anode Tamer, Mugendramon in Cathode Tamer) in a row. Upon being defeated by Akiyama Ryo, Yagami Taichi is freed and returns to his own world, finishing the game.
Millenniumon appears as the final boss in the game.