Checkmate is trained by Sunshine, in which he is expected to take revenge on the New Generations. He is impervious to pain, but can still be injured and harmed, and has the ability to change form according to button presses on his chess-piece shoulder-pads. He can take the form of a castle or the form of a horse (rook and knight respectively). After being defeated by Mantaro, he becomes a Seigi Chojin. It as at this point that he becomes a supporting character in the anime, where he often appears as comic relief or providing commentary for matches.
d.M.p ArcCheck 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 gruelling 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. Sunshine infuses Checkmate with his essence, giving him strength to fight instead of Rex King.  Mantaro is set to battle Checkmate in the next round, but decides against this out of fear, until the popularity polls are released and Checkmate outranks Mantaro.  This reinvigorates Mantaro fight.
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. It is when he applies a newly invented hold, that Checkmate reveals his attacks are ineffective, as he is impervious to pain.  Check Mate proceeds to dislocate own joints to escape Mantaro's submission hold. He proceeds to dominate the match, often damaging Mantaro while Sunshine cheers and supports him from the ringside. 
After Checkmate sees that Mantaro is of little threat, he turns against Sunshine and prepares to murder Mantaro even when Sunshine expresses horror at this turn of events (still abiding by an old honour code). A young child runs up and starts to attack Checkmate, at which point Sunshine intervenes to save the child - Checkmate proceeds to attack Sunshine.  The crowd grows rowdy in their disapproval of Checkmate's actions, but Checkmate is indifferent to their protests due to a lack of emotion. Mantaro intervenes to protect Sunshine.
True to Sunshine's previous warnings, even though Check Mate could not feel Mantaro's attacks and holds, they were still taking a toll on his body. As a result, his knee spasms from the damage it had taken.  Check Mate activates all three of his heads, which exerts enough force that it could kill an opponent due to his sheer strength and weight, and continues to put Mantaro in a High Horse Driver hold in an attempt to finish him. Mantaro breaks free of the attack when the crowd cheers for him, attacking Checkmate's injured patella until it explodes with blood.  Mantaro escapes to perform his own Kinniku Buster, which knocks-out Check Mate and wins him the match.  Sunshine refuses to allow anyone to touch the injured and defeated Checkmate, but proceeds to carry him out of the ring with a promise to train him to be stronger. 
Kajiba no Kuso Djikara Arc
Checkmate makes his first appearance in the west entrance of the stadium.  His presence intimidates Mantaro Kinniku, but Mince offers him a seat beside him and states Checkmate is no threat, and - when Fork the Giant attempts to attack Mantaro outside the ring - comes to Mantaro's defence and blocks an attack.  Checkmate claims to be neutral, and is merely stopping an illegal move, before he admits that his defeat at Mantaro's hands changed him; he desires a good fight over hatred and victory. 
Checkmate follows Mantaro to his next match, which is located in Kyoto.  He changes into street clothes and blushes at some geisha, before it is revealed Mantaro is too weak from his match to fight in the next round.  He watches the Hanzo vs. The Ninja match alongside Mantaro.  After Mantaro wins against Fork the Giant and Hanzo, Checkmate joins his teammates to relax and sing karaoke, before they watch a staged fight for entertainment.  Checkmate intervenes when Bone Cold disturbs the match, and saves the life of Mince from assassination. 
Choujin Olympics: The Resurrection
Checkmate is paired with a person named Shinya, who - being unfit - worries that they are holding Checkmate back and preventing him from winning, and it is revealed Checkmate picked them for being his biggest fan and believes in their inner strength.  Mr. Gacha then attacks them, but Checkmate turns into knight-form and evades the attacks. This accidentally adds further damage to Shinya. To protect Shinya, he cuts the ties that bind them and allows himself to be disqualified, and carries Shinya to safety. 
Demon Seed Arc
After Mantaro'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 Chojin Tag Tournament
Check Mate is one of the Time Warp 8 and travels back in time to the days of the Legends (right after the Dream Chojin 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 time-ship 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.
- Chess Piece Change (チェス・駒・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) Checkmate's normal human form, the form most seen.
- ♞ Knight (馬): 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): 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.
- 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)
- Favorite Food: Gōyā Chanpurū, Yudofu