Devimon is a Champion Digimon, although a very powerful one, rivaled only by Angemon. He is a black demon with horns and red eyes and two wings with holes in them. When he fights the DigiDestined in giant form, his wings spread out like VenomMyotismon's.
Devimon created the Black Gears and implanted them in good Digimon to turn them evil. Victims included Meramon, Andromon, Monzaemon, Unimon, Frigimon, Mojyamon, Centarumon, Whamon, and Drimogemon. The most notable of his victims was Leomon; while Leomon and Ogremon were fighting, Devimon commanded them to work for him. It took little convincing to get Ogremon on his side; however, Leomon was good so he refused to work for Devimon, until Devimon used the Touch of Evil to turn Leomon evil.
The Digidestined confronted him on top of Infinity Mountain, and even used their Digivices to free Leomon from his control. Devimon used his power to break File Island apart and scatter it all over the sea. He also turned Leomon evil again. After fighting off several Digimon, most of them victims of the Black Gears, the Digidestined (minus Joe and Sora) fought Leomon at Primary Village, where Leomon was attacked by more Black Gears, making him bigger and stronger. But they drove all the evil out with their Digivices. Leomon told them that the only way to restore File Island to normal was to defeat Devimon.
Naturally, the Digidestined chose to attack him. Devimon absorbed Ogremon and all the Black Gears, transforming into a much bigger form. Although they were able to get some shots in, Devimon gained the advantage over all of them, using attacks of pure evil. Leomon was sent flying far away by Ogremon, who kept on jumping out of Devimon's chest. Devimon eventually turned to TK, whose Digimon Patamon had not participated in the fight due to his inability to Digivolve.
It was said that the smallest Digidestined would destroy him, so Devimon tried to crush TK but Patamon jumped in front of him and was caught in Devimon's fist. However, it was at that moment that Patamon Digivolved into Angemon. In the classic angel vs devil battle, Angemon knocked Ogremon out of Devimon and put all his power into a Hand of Fate, which he used to destroy Devimon. Angemon appeared to be destroyed as well, but de-digivolved into a Digi-egg. The next time he became Angemon was to fight the equally sinister Myotismon.
When the Digimon Emperor extracts DNA from Digimon to make Kimeramon, he enters the Dark Whirlpool, where he finds the broken remains of Devimon and absorbs them, ignoring his warning that he cannot control the power of darkness. The Dark Whirlpool is said to be caused by Devimon. It is assumed that Devimon returned as some sort of ghost, as his form is incomplete, and is once again destroyed when Magnamon obliterates Kimeramon.
A Fallen Angel type Digimon who wraps his body in jet-black clothes. He was originally a pro-brilliant Angemon, but soon the space of the Digital World became distorted, and he fell into the newly-formed Dark Area and became the fallen angel we see today. On his chest is embodied greatly a mark of evil, proof of his wicked wellbeing. He has a cunning and brutal nature, but he is also very superior and intelligent. It is said that should you be influenced into staring at his crimson-shining eyes, he will control your mind. His special attack is "Death Claw", which stretches out his elasticized arms fully and stabs them into the opponent's heart.