- Classification: Akugyo Choujin→ Seigi Choujin
- Homeland: Monaco
- Height: 221 cm
- Weight: 190~800 kg
- Choujin Kyoudo: 1,210,000 Power
- Trademark Techniques: Chess Piece Change, Stallion Style Honorable Driver, Black Neigh of Centaurus
- First Appearance: Manga Chapter 20, Anime Episode 13
- Chess Piece Change (チェス・駒（ピース）・チェンジ) A special power which allows Checkmate to use the two chess pieces on his shoulders to alter his form and power.
- King (王（キング） Checkmate's normal human form, the form most seen.)
- Knight (馬（ナイト） Used by pushing a button on the Knight piece on his left shoulder, it causes the piece to replace Checkmate's head and and his lower body to turn into that of a horse, making him a sort of Centaur. in this form, he is able to move much quicker and use all four of his horse feet for more powerful kicks.)
- Rook (城（ルーク） Used by pushing a button on the Rook piece on his right shoulder, it causes the piece to replace Checkmate's head and his entire body turns to solid stone, making him harder to damage and allowing him to use the stone body to inflict more damage during attacks.)
- Grand Slam (グランドスラム Checkmate's ultimate move, used by pushing both the Knight and Rook buttons at the same time, it causes his face to turn to a face with King crowned with rook's to part on the left half, and Knight on the right half, his lower body becomes that of a horse like in his Knight form, and his body gains the stone properties of his Rook form, as well as symbols on his body, a simple crown on his lower waist, two horse heads and a much more detailed crown on his chest, and a rook castle on both shoulders. This move allows him to combine his powers such as combining the tactical skill of his King form and the speed of his Knight form with the near indestructible stone body of his Rook form.)
- Stallion Style Honorable Driver (馬式誉れ落とし, Uma-shiki Homare Otoshi)
Used in Checkmate's Knight and Grand Slam forms, he grabs an opponents arms, and leaps up, carrying them up in the air, he then throws them upside down, and as their falling, places his front horse feet onto the bottom of the opponent's feet and pushes down, slamming the opponent into the mat while using his speed to increase the speed of the fall and the power of the impact.)
- The Centaur's Black Neigh (ケンタウロスの黒い嘶き, Kentauros no Kuroi Inanaki)
- Gallop Kick (ギャロップキック)
- Rook Sky Twister (ルーク・スカイツイスター)
- Open The Rook Gate (オープン・ザ・ルークゲート)
- Close The Rook Gate (クローズ・ザ・ルークゲート)
- Separate Body (解体城（セパレーツ）ボディ)
- Blood Binding Windows
- Used in the Grand Slam form. Little openings on Checkmate's thighs and chest which trap the ankles and hands of an opponent. Followed up by the Human Desk Bomb Drop.
- Window Blinds
- Human Desk Bomb Drop (落爆人机, Raku Baku Hito Tsukue)
With his opponent trapped and his front exposed, Checkmate jumps and falls facing the mat, crushing the opponent trapped in front of him.
- King Style Brilliant Throw (王式絢爛投げ, Ou-shiki Kenran Nage)
- A V-Jump technique. Essentially a double underhook facebuster.
Stallion Style Honorable Driver Story
Check Mate was just a homeless kid on the streets when he happened to run into veteran devil chojin Sunshine, who saw potential in him and decided to train him to become a perfect chojin. Sunshine used grueling techniques to teach the boy not to feel any pain of any kind, and forget words like failure or defeat. After the battle with Rex King, Terry the Kid was in no condition to take on Check Mate. Mantaro was to fight him, but chickens out. However, after Check Mate comes in first place in a favorite wrestler poll amongst the women and he's ranked dead last, Mantaro decides he must defeat Check Mate--for the girls.
In the match's early moments, Mantaro appears to be in control as he unleashes a barrage of nonstop attacks on the barely-resisting Check Mate. But as he applies an impressive new hold he's invented, Check Mate reveals that it's completely ineffective--as were all of Mantaro's attacks, because he can't feel pain. Check Mate proceeds to dislocate his own joints to escape Mantaro's submission hold. He then proceeds to dominate the match, wiping the mat with Mantaro as Sunshine cheers and wishes his old devil chojin friends could watch the defeat of the son of Kinnikuman. But as Check Mate sees how little of a threat Mantaro is, he wonders what kind of weaklings could have possibly been defeated by this oaf or any of his kin. He turns on Sunshine and prepares to cripple or kill Mantaro with an elbow drop on his neck, which is resting on a jagged board. A young child runs up and starts yelling and hitting Check Mate--who promptly turns and smacks the boy away from him. By now the crowd has turned completely, and they throw things at Check Mate and cheer Mantaro. Because he has no feelings, Check Mate doesn't care about this and continues fighting Mantaro, who's beginning to recover. At the crux, Check Mate activates all three of his heads and puts Mantaro in a Stallion Style Honourable Driver in an attempt to finish him...but as Sunshine was trying to warn him, even though Check Mate wasn't feeling Mantaro's many attacks and holds, they were still taking a toll on his body. As a result, his knee spasms from the horrible damage it'd taken, and Mantaro escapes to perform his own Kinniku Buster, which KOs Check Mate
Choujin Olympics: The Resurrection
Demon Seed Arc
After Mantarou's loss to Kevin Mask, Check Mate, Kid, Seiuchin, and Gazelleman try to cheer him up. He and Gazelleman later sit at ringside for Kevin Mask's and Scarface's fight with Ashuraman and Voltman. He also joins forces with Jade to help Kevin train for his match against Voltman.
Ultimate Choujin Tag Arc
Check Mate is one of the Time Warp 8 and travels back in time to the days of the Legends (right after the Dream Choujin Tag Arc conclusion) in order to save Robin Mask from being killed and, by extension, Kevin Mask from being erased from time. During the construction of the timeship he is part of Team 2, who are to retrieve the spherical section of the Fujiyama TV headquarters for the cockpit of the ship. On the day of departure, he brings an abundant amount of protein pills and drinks. On the ship he is placed in charge of the air conditioning.
When the Ultimate Choujin Tag Tournament is announced, Check attempts to team up with Seiuchin, but Seiuchin refuses, believing that he is not worthy. When Seiuchin leaves with Neptuneman, Check follows and witnesses Seiuchin's beastly transformation. He overhears Neptuneman speaking of a Perfect Choujin Revival and attacks him with his Black Neigh of Centaurus. However, Neptuneman proves too powerful and Check Mate is soon defeated with a Cross Bomber so powerful the skin of his face peels off. Neptuneman and Seiuchin carried Check Mate in a coffin during the Opening Ceremony for the tournament.
Recently, a shadowy figure with boots and a cape similar to Check Mate's was seen boarding a bus heading for the tournament.
- Favorite Food: Gōyā Chanpurū, Yudofu
- 1st Kinnikuman Nisei ~All Choujin Dai Shingeki~ Popularity Contest (6th Place)
- d.M.p Nightmares No. 2
- Idol Choujin
- The 8 Time Warp Choujin
- Invulnerable Choujin (不死身の超人, Fujimi no Choujin)
- High Limits Choujin (極限の超人, Kyokugen no Choujin)
- Win/Loss Record (Singles)
- O Gorgeousman (???)
- X Mantarou Kinniku (Kinniku Buster)
- O Awesomeman (Stallion Style Honorable Driver) Choujin Olympics qualification match
- Δ Captain Macko (King Style Brilliant Throw→ Double KO) (V-Jump)
- Win/Loss Record (Tag)
- X Hell Expansions (Optical Fiber Cross Bomber)
- Win/Loss Record (Other)