Kamata (鎌田) is Kamen Rider Abyss (仮面ライダーアビス Kamen Raidā Abisu), a fictional character in the 2009 Kamen Rider Series Kamen Rider Decade. Unlike other Kamen Riders to appear in the other iterations of reality in Decade, Abyss is original to the series and did not originally appear in Kamen Rider Ryuki, although his Contract Monsters, Abysshammer and Abyssslasher, did.
Kamata is actually the Paradoxa Undead (パラドキサアンデッド Paradokisa Andeddo), a Category King Undead who was brought into Ryuki's World by Narutaki. Assuming the guise of sub-chief editor of the Atashi Journal appeared to support Tsukasa and company in their investigation the scene of chief editor Reiko Momoi's murder to clear Natsumi Hikari, helping provide whatever info he could before he and Tsukasa are summoned to join the Kamen Rider Trial in the Mirror World.
When Imperer interferes in the fight, Abyss decides to take advantage of this turn of events to see Decade's abilities, overseeing the later fight between Decade and Knight before attempting to take them and Ryuki out. But once Ren acquires the Time Vent from Odin, Shinji uses it so he and Tsukasa can stop Reiko's murder, learning that Kamata is the culprit, using his Undead powers to kill Reiko. After being defeated by Decade and Ryuki, with his deck shattered, Kamata's true nature as an Undead is revealed by Narutaki who takes him back to his home: Blade's World.
Kamata returns to the World of Blade where he works with Hajime in a plot to take over the world as the chairman of the BOARD Corporation. After helping Hajime steal the three other Rider Systems, Kamata helps him create the Joker Rouse Card. He is later defeated alongside the Joker by Decade and Blade.
In the World of the Rider War, a copy of the Paradoxa Undead was created by Super Apollo Geist by combining Undead. This Paradoxa Undead is destroyed by Kiva.
Some time after his original destruction by Decade and Blade, Kamata is resurrected by Narutaki, and is given a new Abyss deck, which re-initiates his contracts with AbyssSlasher and AbyssHammer
Initially appearing kind towards Shinji and Tsukasa, he revealed his true nature, revealing himself a cold-hearted monster, willing to torture and kill to reach the desired end. After his resurrection, this behavior pattern has not changed.
- Height: 187cm
- Weight: 92kg
- Ability perimeters:
- Punching power: 10t
- Kicking power: 15t
- Maximum jump height: 30m
- Maximum speed: 100m/5 seconds
Abyss is unusual amongst the Kamen Riders in that he has two Contract Monsters: the Abysslasher (アビスラッシャー Abisurasshā), a humanoid shark that can fire high pressure streams of water, and the Abysshammer (アビスハンマー Abisuhanmā), a humanoid hammerhead hark. As Kamen Rider Abyss, Kamata uses his Final Vent to combine his Contract Monsters into a creature known as Abyssodon (アビソドン Abisodon), a single giant mechanical shark with a chainsaw attachment (giving it the appearance of a sawshark when in use) and machine gun eyes (giving it the appearance of a hammerhead shark when in use). Unlike other Riders in the Mirror World, the loss of the Contract Monsters did not result to Abyss going into Blank Form.
- Height: 227cm
- Weight: 127kg
- Ability perimeters:
- Punching power: 25t
- Kicking power: 30t
- Maximum jump height: 60m
- Maximum speed: 100m/4 seconds
As the Paradoxa Undead, Kamata is reverted to a more feral state of mind, attacking his opponents without mercy or warning. In this state, his stats are boosted, but he loses most of his strategic thought process in battle.