|Robot||Mazinkaiser SKL w/ Ryo Magami|
|Family and Relations||Ryo Magami (Partner)|
|Voice Actor||Shintarō Asanuma|
|First Appearance||Mazinkaiser SKL Versus chapter 1 (Manga),
Death Caprice (Anime)
As revealed in Mazinkaiser SKL Versus Kaido was an inmate in a detention center who regularly beat the other inmates when they picked a fight with him. A scientist from WSO working on the Mazinkaiser SKL picked him out to participate in the experiment to pilot the Kaiser. Kaido disliked the idea of being a guinea pig but the scientist convinced him when she told him that all other applicants failed and nearly committed suicide, including herself. Fascinated by the challenge, Kaido accepted. As Kaido took the controls he could feel the immense power of the Kaiser as it felt like it was tearing him apart. But Kaido hung on and managed to move the Kaiser's limbs, surprising everyone including the scientist. When the test was over, he noticed another man sitting behind him. As he argued with the stranger, the scientist had the Kaiser moved to another area. Before they landed, Kaido got the name of the other man, Ryo Magami. Soon the Kaiser was dropped off at an area full of robots piloted by convicts. The Kaiser tore through them all, with Kaido taking a piece of an enemy robot as a weapon. Soon they join the Skull Force by some unknown event becoming the Death Caprice Squad.
The OVA presents a different backstory where he encountered Magami and they teamed up to become mercenaries with a myriad of titles of their brutal reputation. Afterwards they are recruited by WSO to join Skull Force to pilot the Kaiser.
Kaido for the most part resembles Koji Kabuto, the pilot of the Mazinger Z and in some cases the original Mazinkaiser. However, his hair is colored a lighter black, with his eyes the same color. His skin is also a little pale, but not as much as Ryo. Kaido wears the Skull Force uniform with the jacket's sleeved torn off and the jacket open with no shirt underneath showing an athletic build. Instead of a gun holster he carries a dagger and its scabbard.
Kaido is argumentative, hot-blooded, rude, and vulgar, compared to his usually calm and quiet partner. Kaido enjoys fighting more than everything else, always preferring to fight and destroy rather than solve things peacefully, and when he fights he shows little mercy. His recklessness at times causes unnecessary actions such as detaching the Skull Pilder from the Kaiser in the rematch with Kiba. More often then not, he makes wise cracks even in the face of danger. Kaido does have a sense of respect however, staying close to Ryo as his partner and was disappointed when Scarlet Hibiki was killed in a crash.
True to his name, Ken is highly adept in bladed weaponry. He carries a large assortment of knives and a katana with a skull for decoration. He is able to take down several opponents at once with his skills, even match Garan. For long range, rather than guns, he uses throwing knives.
As one of the pilots of the Kaiser, Kaido pilots it whenever the Kaiser uses the Ganzanto, or fights in close combat. His skills in piloting the Skull Pilder are just as great, pulling off maneuvers and effectively using its weapons in a dog fight.
Kaido and Magami were often sent on missions with the Kaiser throughout the course of the SKL Versus manga, to deal with serious threats that were usually giant robots or monsters as well as a group lead by Faust. Soon they are sent to Machine Island prior to the Gren Falcon Squad but their transport lost control due to the Gravity Curtain. The Death Caprice Squad managed to survive and had to deal with obstacles including Kiba and Garan's army. They brought a girl with them who proved to be a helpful ally as she managed to break free as the reigns on her and hold off forces.
Their mission soon began to go forward with the arrival of Tsubasa Yuki, the only survivor of the Gren Falcon Squad after their transport had a similar incident. On Machine Island, Kaido and Magami would fight the more diabolical rulers of the island, Kiba and Garan. With Garan putting them in a pinch, they managed to get back up and deal the finishing blow. Unfortunately, Kiba who survived their last encounter was still alive and gained control of the Iron Kaiser, a robot with the same power source as the curtain. With this revelation, the gravity curtain became more unstable and the Death Caprice Squad had to fight the Iron Kaiser (they didn't mind and preferred to destroy the curtain). With the power up from the Wingle, the Kaisers were nearly matched but the SKL managed to drag the Iron Kaiser to the core of the Gravity Curtain where the Squad destroyed it along with Kiba. With this mission accomplished, they move onto another mission with Tsubasa as their captain.
After Machine Island, Kaido and Magami had fought against Faust's group again as well as one of the clones that Magami had come from. With the enemy forces at work, the clone launched the final robot to fight Kaiser. With Kaiser at full power, and both the Death Caprice Squad leaving the past behind them, they defeat the clone and destroy his robot.
'Ken' is Japanese for sword, referring to Kaido's preference for blades and his skill in using them both in and out of SKL. His codename possibly comes from the demon character Amon who Akira Fudo combined with to become Devilman. For most of the manga, he was partnered to the fallen angel Satan where Ryo Magami's codename comes from.