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Nightmare Fuel: Kinnikuman
Being a cyborg is not all that it's cracked up to be.
As expected from a wrestling manga, when the violence gets bad in this series, it tends to get really bad. Despite that, there's a surprising amount of generally scary things and some And I Must Scream fates for any poor soul who happens to be on the losing end of a match.
A side-effect of the cartoony art and extremely gory violence is that any time the series features a particularly vicious move, you can just feel it. Someone's getting torn open, or impaled, or twisted until their spine breaks? Ow. And keep in mind that, in this series, this kind of thing is just ordinary wrestling.
The match between Mr. Khamen and Brocken Jr. when Mr. Khamen uses his finishing move on the referee, by accident. Mr. Khamen's special involves wrapping the opponent in cloth and then mummifying them by sucking out all the water in their body until they become a dried husk. It doesn't really help that he overdid it; he sucked up so much moisture of the victim that he even sucked up his skin. It's so disturbing and unsettling that it makes many a reader really wonder how Mr. Khamen wasn't the Big Bad of that arc. note Thankfully it's made less disturbing in the anime; the referee was replaced by Kinkotsuman, who apparently wasn't affected AT ALL.
The worst part? Mr. Khamen was a Devil Choujin, meaning he was banned for killing too many opponents.
His match against Kinnikuman in the anime is no better either. As it begins, he's breathing heavily through his mouth, has an evil glint in his eyes and he's laughing. In short, they made it look like Kin was going up against someone who should be in a straitjacket rather than in a wrestling ring.
In the anime, surprisingly we have Kinnikuman's match against Curry Cook. While you think that Kin's just being a coward as usual when he tries to escape the ring enclosed in a steel cage, but then we get a good look at Curry Cook...and let's just say that the anime did a really good job of how scary someone should be if they kill opponents for fun in a sport.
Speaking of Ramenman, you want to know what becomes of him in the next Choujin Olympics? It's not pretty. His brain gets pierced by Warsman's bear claws, reducing him to a vegetative state.
The final of the 21st Choujin Olympics gives us a good example of Body Horror, where due to match regulations, Warsman has to remove his mask after losing, as shown at the top of the page. Yeah, we're pretty sure that Harabote must be kicking himself for making up that rule.
In the Throne Arc, we have the origins of Parthenon, a Choujin from Greece, which consisted of the young men that built him being honored by being entombed alive in his pillars. Worst of all, Parthenon can dissolve his pillars and regenerate them in order to trap opponents inside of them as an attack, knowing that those pillars are filled with methane and other gases given of from the decaying bodies, ensuring a slow Fate Worse than Death for the opponent if they can't get out.
"Crazed Robin Mask". During the 20th Choujin Olympics Finals, Robin cracks his mask against a ringpost, causing him to bleed profusely. The panel of him glaring at Kinnikuman, declaring his intent to kill, as blood pours out from under the mask kills any remaining vestige of the "superhero parody" stretch of the series. Shortly after this, Robin goes berserk.
The Most Evil Combo in the Universe literally dismembering Black Shadow, starting by tearing his arms off.