Millenniumon

Level - Ultimate (Japanese), Mega (English)
Attribute - Virus
Type - Synthetic (Mille)/Evil God (Moon-Mille)
Attacks - Time Unlimited, Dimension Destroyer (Mille); Death Crystal, Dimension Destroyer (Moon-Mille); Time Destroyer, Chrono Paradox (ZeedMille)
Forms - Millenniumon, Moon-Millenniumon, ZeedMillenniumon | cards
Bases - Millenniumon's Sanctuary (Anode/Cathode), Millenniumon's Castle (Tag), Last Tower (D-1), Millenniumon's World (Brave)

Extra information - Due to a bond with Ryo that was not mentioned until the end of D-1 Tamers, Millenniumon cannot truly die. He says himself that he is the shadow to Ryo's light, and that one cannot exist without the other. He is Ryo's true digimon partner, as revealed in Brave Tamer. Though he was born of the fusion of two chimeras, he has always referred to himself in the singular; at first he refers to himself as "watashi" (formal "I"), then as "ware" (lordly "I") in later games.

Born of the jogress of Chimeramon and Mugendramon in the time between the end of Season 1 of the anime and the beginning of Anode Tamer (Dec. 31, 1999), he eventually came to power and was successful in abducting all the Chosen Children of the first season. A normal boy was sent to destroy him, one without a digimon partner or digivice of his own. A boy who turns out to be the only one capable of defeating Millenniumon when even the Holy Beasts could not. He eventually figures it out: this boy with nothing to call his own was his human partner all along.

For the first few games, all the player knew of Millenniumon was through his rare interactions with Ryo and dialogue from various digimon and Gennai/Piccolomon. Millenniumon appears in person only once in Anode/Cathode: at the last floor of the final dungeon. Much like Zeromus in Final Fantasy IV, Millenniumon here says standard villian threatening dialogue and is defeated. In Tag Tamers he appears immediately after Ryo responds to the sudden appearance of a severely weakened Diablomon in the Digital World, revealing a bit of rather creepy obsession. He used Diablomon to lure Ryo to him and says that he had been waiting for Ryo's return. He then blows up the mountain on which they were standing and this action splits the Digital World in two. Then of course is the final dungeon in Tag Tamers, as well as the final dungeon in D-1 Tamers. In both cases, he addresses Ryo more and more as his equal.

It's in Brave Tamer that his personality is truly shown. No longer can he be considered just a mindless killer, he is shown with motives that suggest significant foresight. He is brilliantly intelligent in his plots and speaks in a rather cultured manner, yet his own minions call him on the fact that he's been ignoring the resistance to his rule for "playing" with Ryo. Despite the revelation of his love for Ryo (he refers to Ryo as his beloved ("ware no koibito") near the end of Brave Tamer), he doesn't seem to understand that his games have a damaging impact on the boy and believes that they are doomed to battle each other for eternity. He is capricious when he wants to be, and vindictive in that he lets the minion who questioned him go to be defeated by Ryo. He also displays the true depth of his obsession.

Millenniumon had been obsessed with having his revenge from the first time Ryo defeated him, though by the end of Brave Tamer, the idea of whether or not that was truly the case is suddenly in question. His own minions call him on his obsession with Ryo: a SkullSatamon asks him to stop playing with Ryo and please take things more seriously, Lampmon openly questions just what kind of interest Millenniumon has in Ryo. By the end of the game, he seems to be proud of how far Ryo has progressed. In the end, this obsession with Ryo gets the better of him: it allowed Monodramon to force a Jogress so that they could both be Ryo's partners. The jogress ended up in an egg at the end of the game, and presumably evolves to Cyberdramon.

Other published data -

(from Koushiki Daizukan Volume IV, published by V-Jump. Page 43)
Number: 216
Name: Millenniumon
Level: Ultimate
Type: Virus kind, Composite type
Certain Kill Skill: Time Unlimited
Strong Point Skill: Dimension Destroyer
Location: World of Darkness
Favorite Food: Tsubame no Su (*)
Likes: Millennium commemoration goods
Hates: That the festival (New Year's, I assume) isn't celebrated daily

(*Note: Tsubame no Su is basically Bird's Nest (soup), which is made from the purely gelatinous nests made by certain species of sparrows using only their gummy saliva. It is considered an aphrodisiac in most countries in East Asia, and "tsubame" is a slang term often used in reference to someone's younger lover {complete term is "wakai tsubame".})