Ichijouji Ken

Profile
Ken is a sweet boy, very kind and polite towards others. He became a Chosen Child to fight a threat to the Digital World several years before the other Adventure 02 Chosen. He is haunted by the death of his elder brother and everything he did as the Digimon Kaiser.

Ken's Digimon Kaiser persona is cruel, cold and sadistic, enjoying nothing than causing pain to others and seeing them suffer. This persona was fueled by a corrupting Dark Seed planted in the back of his neck.

Digimon Adventure 02: Tag Tamers
During Tag Tamers, Akiyama Ryo and Ichijouji Ken are called to the Digital World soon after the battle with Diablomon in Digimon Adventure: Our War Game, after it appears to escape to the Digital World. There, Ken meets his partner Digimon Wormmon, and Ryo 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 Ryo back into the Digital World, after which Millenniumon destroys Mugen Mountain, causing the Digital World to tear into two.

During the remainder of the game, Ryo 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 took it and hid it away in his desk drawer, 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. At the same time in the Digital World, Ken started excelling in his studies and became very athletic, becoming famous in Japan as a boy genius, much like Osamu was before him.

Eventually, opposition to his regime came in the form of the new Chosen Children, who hadn't realized he was the famous Ichijouji Ken. In turn, he hadn't realized that they or their Digimon were real, thinking it was all a game.

After some time, Ken's Tamachi FC soccer team were scheduled to play a game against Odaiba Elementary's team. Ken arrived only for the second half, but brought his team to victory. During the game, he saw the Chosen Children with their Digimon in the audience, and played against Daisuke, but hadn't realized yet that the Digimon he was fighting were all real beings. A tackle from Daisuke injured Ken's ankle during the game, and in retaliation, Ken (as the Digimon Kaiser) had Daisuke degrade himself, threatening to feed the Chosen Children to Deltamon. However, the real Chosen Children appeared, revealing the deception. Daisuke tackled the Kaiser in a scuffle, and during the fight, he recognized the injury on the Kaiser's leg, prompting Ken to reveal himself as the Digimon Kaiser.

After this, Ken ran off to the Digital World, determined to purge his opponents and take full control of it. He developed the Evil Spiral to control Perfect Digimon and used in on Taichi's Agumon, but his tainted D-3 only managed to evolve the Digimon to Skull Greymon. After Wormmon helped Agumon escape, Ken recaptured him and finally made him evolve into a dark Metal Greymon. However, the Chosen Children managed to bring Agumon back to them with Daisuke's new Digimental of Friendship.

From this day on, Ken started working on creating a synthetic Digimon he named Chimeramon. He sent Chimeramon out to wreck havoc around the Digital World, but eventually, Chimeramon proved too violent for him to fully control. To save the Digital World and Ken, Wormmon helped Daisuke to locate the Kaiser's base's engine room, where he discovered the source of its energy, the Digimental of Miracles. Daisuke used it to Armor Evolve V-mon to Magnamon. When Daisuke unlocked the Digimental, V-mon noticed that a crest is inside of it, which was later revealed to be Ken's Crest of Kindness. Although Magnamon was powerful, his true power was not revealed until Wormmon gave him the energy to defeat Chimeramon using his Extreme Jihad attack. Daisuke and the others finally made Ken realize that Digimon were real, living things, not just computer data, a point driven home by the death of Wormmon. He shed his Kaiser persona and 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. He even invited them all to a Christmas party, though it was cut short by an invasion of Digimon.

On Christmas Day, the Chosen Children found out that Digital Gates were open in the entire world. Qinglongmon gave the Chosen Children one of his Digicores to help power up the Digimon, enabling Paildramon to evolve into Imperialdramon. Ken and Yamato went to Mexico to help the local Chosen Children round up the wild Digimon that had come through the gates.

Back in Japan, the children had to fend off the Demon Corps, a group of evil Digimon led by Demon. The others' Perfect Digimon gave Imperialdramon the power they got from Qinglongmon he mode changed into Imperialdramon Fighter Mode, and with this power, Imperialdramon destroyed Skull Satamon. Following this, Archnemon and Mummymon showed up with a truck full of kids they had rounded up, and coaxed Ken to come with them. In the truck, he met their boss, Oikawa Yukio, who revealed to him that he had been manipulating Ken in his Digimon Kaiser days using the Dark Seed in Ken's neck. Oikawa proceeded to scan Ken's Dark Seed and implant the copies in the children. The truck was stopped in Hikarigaoka by Demon, who demanded to have Ken. Ken used his D-3 to opened a gate to the World of Darkness, with the help of the other Chosen Children, and banished Demon there. However, Oikawa managed to run away.

Ken and the others followed the seeded children for the following days, facing Oikawa several times. On December 31st, they followed Oikawa and the children to the world of dreams, where it was revealed that Oikawa Yukio was possessed by the spirit of Belial Vamdemon, who absorbed the power of the Dark Seeds to gain a corporeal form. He killed Archnemon and Mummymon, which shocked and frightened Ken and the others. When Daisuke and XV-mon started fighting back, BelialVamdemon subjected the children to an illusion, showing their greatest desire. Ken had two desires; to see his evil Kaiser self punished and destroyed for all his bad deeds, and to be with Osamu again. However, the dream Osamu and Wormmon told Ken it was just a dream, and all the Chosen Children and their Digimon appeared to take bring him back to reality. When everyone's illusions were broken, Ken used the power of the dream dimension against BelialVamdemon, with Stingmon, Paildramon, Imperialdramon and Imperialdramon Fighter Mode appearing all at once to fight BelialVamdemon. After BelialVamdemon escaped to the Digital World, the light from his D-3 helped weaken BelialVamdemon and power up Imperialdramon Fighter Mode's Giga Death cannon.

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.