Every Superhero has his/her Archnemesis.
Superman/Lex Luthor
Batman/Joker, Penguin, Riddler
Shazam/Dr. Sivana, Mr. Mind, Black Adam
Aquaman/Black Manta
Who is Plastic Man’s Arch Enemy?
Himself, largely.
Doctor Dome?
Yeah, himself.
Note just how powerful plastic man actually is. He doesn’t become the shape of a jet engine, he actually becomes a jet engine and flies around.
The only thing saving the DC universe from his plasticky hegemony is his own mania and lack of focus.
Many comic afficianadoes (sp?) are probably unaware how powerful Plastic Man truly is. His physical capabilities are on par with whatever Green Lantern can come up with…bar flying in outer space at the speed of light.
Aside from the stated vulnerabilities to extreme heat and cold, he probably also couldn’t handle mega-strength nor hyper-speed, so battle against Reverse-flash or Doomsday is out.
Just about anybody else in the Legion of Doom could quickly fall against his might: Imagine Luthor, Penguin, Black Manta, etc. simultaneously being punched by ten fingertip fists stretched out from the other side of the room.
IIRC, he faced the future Flash in the One Million story – and said Flash didn’t realize he was in a room that is someone, and promptly got hit from behind for the win.
Woozy Winks. He’s playing the long con.
You guys have all read the hilarious Kyle Baker reboot series from the ‘00s, right? It might not be Plastic Man Canon, but it’s great stuff!
No plastic jet engines in THIS world…if Plas wants to fly, he has to suck helium and turn into a dirigible.
Eel O’Brien.
Dr. Forklift, the cyborg centaur!
In a Justice League tale, when the Martian Manhunter went berserk after trying to cure himself of being afraid of fire, all the heroes fell to J’onn. That’s when Batman pulled out his secret weapon: Plastic Man. Along with all of his other skills, Plas is immune to mind-control because he’s basically inorganic. All Berserker-J’onn had to match Plas, really, was shape-shifting, and, as Bats told Plas: “He has no imagination.”
Game, set and Plas.
Testor’s Plastic Model Glue.
Or Dr. Cragle.
According to Mad magazine back in the 1950s, COLD:
Plastic Man had lots of nemeses back in the comics in the 1940s – how could you be a superhero without them? – but no one major Professor Moriarty-like threat that I’m aware of. Of course, I’ve only read a handful of the actual original stories.
Aplastic anemia.
To be accompanied by ‘Box of Kitchen Matches Man’ (ahhh, those wonderful flaming, sizzling droplets).
Believe it or not, I remember reading the story “The Hamsters of Doom”.
From his TV Show—Disco Mummy!