Mammothman is a mammoth chojin who appeared as a member of Kinnikuman Super Phoenix's team during the final story arc of the manga. His trademark was extending tusks that seemed to have a mind of their own, and would seek out and consume any exposed blood nearby.
He reappears in Kinnikuman Nisei disguised as the teddy bear Michael, teaming up with Warsman as his tag team partner to form the "Hell's Bears". His identity was hinted at when Neptuneman tasted and recognized the ice that fell out of Michael's costume.
Mammothman first appeared at Kinnikuman's coronation, where he prevented Kinnikuman from attacking Super Phoenix, his master. In the first round of the tournament, he quickly showed his power by slaughtering Kinnikuman Big Body's entire team, but tied on purpose with Cannonballer to allow Super Phoenix to be the one to fight Big Body. Mammothman next saw action in the six-man match between team Super Phoenix and Team Soldier. In a clash of titans he singled out Buffaloman and the two eventually engaged in a battle of possession of Soldier's Muscle Prophecy page. Buffaloman eventually took him out with a Buffalo Bomb but soon after fell to his death into the canyon below. When Mammothman regained consciousness he took the page and threw it into a torch, causing Soldier to begin disappearing. Later, after learning of Warsman's training to defeat the Big Tusks, Mammothman ambushed Warsman forcing him to drop out of the finals.Mammothman's final battle was in another six-man match against Kinnikuman, Neptuneman (disguised as The Samurai) and Robin Mask. For the most part, Mammothman fought Robin, doing a number on the hero with his blood-seeking tusks. To make the fight "more interesting," Super Phoenix started to burn the pages of both of the chojin from the Muscle Prophecy book. The pages' destruction was akin to the chojin never having existed. Robin, master strategist as always, deduced the weakness of the tusks and spilled blood onto Mammothman himself. His tusks turned against him and impaled Mammothman. Robin defeated Mammothman with a Rope Work Tower Bridge. Both, however, disappeared with the immolation of their prophecy book pages, Mammothman crying his hatred for everyone assembled.
Mammothman appears as 21st century Warsman's mysterious partner Michael. During a fit of rage before the second round of the tournament, his costume nearly tore off before Warsman calmed him down. However, the snow that fell out of his costume clued 21st century Neptuneman in on his identity.
During their fight against the Hell Expansions, Neptuneman and Seiuchin, his identity is finally revealed and he goes head to head with the Perfect Chojin Seiuchin. When Seiuchin is brought back to his senses, both Neptuneman and Mammothman betray their partners, when Warsman had just defeated Seiuchin, and team up in the middle of the match. They knock off Seiuchin's face with an Optical Fiber Cross Bomber, then they defeat Warsman.
Before the semi-finals begin, Satan appears in the sky, and Neptuneman and Mammothman reveal their allegiance with The Five Disasters Thunder and Lightning, throwing a hell-spawned spider at Kinnikuman, which enters his body and forms into an hourglass.
- Big Tusks (ビッグ・タスク)
- Mammothman's versatile tusks either jut out to pierce, grow more protrusions or home in on his enemies by sensing their blood, which Robin Mask used to his advantage in their match.
- Powerful Nose Breaker (パワフル・ノーズブリーカー)
- Using his trunk he lifts his prey up in the air, then places his knee out and performs a devastating backbreaker on them.
- Nose Fencing (ノーズフェンシング)
- His trunk elongates and becomes pointed at the end, he uses this to impale his opponents.
- Ghost Canvas (ゴーストキャンバス)
- He slams his opponent's head into the canvas so it is stuck, then twists the body until the head snaps off.
- Ice Rock Gyro (アイス・ロック・ジャイロ)
- He lifts up his opponent with his trunks and throw him/her into the air. While in mid-air, the opponent starts to get whipped by Mammothman's trunk. The opponent start to freeze into a solid block of ice everytime he/she gets hit.
- Choujin Decoration Tree (超人デコレーションツリー)
- A combination move with Prisman and Super Phoenix. Mammoth man throws the opponent into the air facing upwards. Prisman catches the opponent in a triangle choke hold while Super Phoenix applies a figure four leg lock at the same time. The opponent then falls onto Mammothman's shoulders and he applies an argentine backbreaker hold as well.
- Team Super Phoenix: Advance Guard (First Round)→ Second Guard (Semifinals)→ Second-in-Command (Finals)
- Chōjin Hunter
- Chōjin Destroyer
- Intelligence Chōjin
- Immortal Body
- Win/Loss Record
- O Pinchman (Powerful Nose Breaker)
- O Leopardon (Nose Fencing)
- O Golemman (Ghost Canvas)
- Δ Cannonballer (Double KO)
- X Buffaloman (Buffalo Bomb)
- O Warsman (Big Tusks)
- Δ Robin Mask (Rope Work Tower Bridge→ Double KO)
Win/Loss Record (Tag)
- O Team Cosmos (Teddy Crusher)