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Intro. Anton Mercer was on the verge of a scientific breakthrough during an experiment involving dinosaur DNA, when he was accidentally transformed into Mesogog, an evil mastermind with plans to revert the earth to the age of dinosaurs and turn the human race into reptilian creatures like himself. As a result of the accident Mesogog and Dr. Mercer were distinct personalities with the same body in a Jekyll-Hyde relationship. Each is aware of the other's existence, but also both dislike their situation (Dr. Mercer, for having a villainous alter-ego that he can barely control and Mesogog, for having a human half holding him back). In his Mesogog form, he was equipped with cybernetic technology and psionic powers that he uses to torture his enemies.

Mesogog

@Conrad