Ichijouji Ken

Digimon Adventure 02: Tag Tamers
During Tag Tamers, Akiyama Ryou and Ichijouji Ken are called to the Digital World soon after the battle with Diablomon in Digimon Adventure Our War Game after it seems a second has escaped into the Digital World. There, Ken meets his partner digimon Wormmon, and Ryou partners up with what will be Motomiya Daisuke's partner, V-mon. Millenniumon appears after the battle and says that the Diablomon was simply meant to lure Ryou back into the Digital World, after which Millenniumon destroys Mugen/Infinity Mountain, causing the Digital World to tear into two.

During the remainder of the game, Ryou and Ken take turns clearing the various fields and dungeons until they arrive at Millenniumon's floating continent.

Digimon Adventure 02
As a child, Ken grew up in the shadow of his older brother, Ichijouji Osamu, a boy genius. One day, when the two were on the computer in their room, a Digivice emerged from the screen, Osamu taking it and hiding it, telling Ken not to touch it. However, the curious youngster touched it anyway, and Osamu punished him for it, taking the Digivice.

Ken wanted nothing more than for Osamu to vanish now, and a little later, Osamu ended up getting hit by a car and dying. Ken was full of sorrow, thinking his thoughts were the reason Osamu died. He dedicated himself to his studies, in an attempt to help his parents fill the void created by Osamu's death.

Following an anonymous email he received while working on Osamu's old computer, Ken took the Digivice again and ventured to the Dark Ocean, where he changed his Digivice into a D-3 and become corrupted. Ken went on to become the ruthless Digimon Kaiser, and began to create the Evil Rings and Dark Towers in order to put the Digital World under his control.

The Digimon Kaiser began to take over much of the Digital World, but had opposition in the Chosen Children. No matter what plan he came up with, whether it be taking control of Metal Greymon or creating Chimeramon, the Kaiser was always defeated.

In his final moments, the Kaiser realized that Digimon were in fact living creatures, a point driven home by the death of Wormmon. He decided to go home and never return to the Digital World.

However, Ken ended up returning to the Digital World and reuniting with a reborn Wormmon, and decided to help destroy the Dark Towers he'd erected to try and make up for what he'd done. Wormmon aided him, finally evolving into his adult form of Stingmon. When he went head on into a hopeless battle against Ookuwamon, Motomiya Daisuke showed up and tried to convince him that he can't go fighting all on his own. Daisuke's words to Ken enabled Stingmon to Jogress with XV-mon and form Paildramon. From this point on, Ken worked with the Chosen Children and eventually became one of their own.

When the Demon Corps attacked, Qinglongmon gave the Chosen Children of his orbs to help power up the Digimon, enabling Paildramon to evolve into Imperialdramon. When the others' Perfect Digimon gave Imperialdramon the power they got from Qinglongmon he mode changed into Imperialdramon Fighter Mode.

Diablomon Strikes Back
Ken was sent with Daisuke to collect Kuramon that Diablomon sent to Earth. When all of the Kuramon fused into Armagemon, Ken and Daisuke used all of Omegamon's remaining power to mode change Imperialdramon Fighter Mode again into Imperialdramon Paladin Mode.

25 Years Later
By 2027, Ichijouji Ken has married Inoue Miyako and had three children with her, going on to become a police officer (detective in the dub) with Stingmon.

Video Game Appearances
Ken and Wormon are playable in Digimon Adventure 02: Tag Tamers, Digimon Tamers: Battle Evolution, Digimon Battle Spirit, and Digimon Battle Spirit 1.5.