The Monster Men were a race of super-beings engineered by Hugo Strange with a growth serum.
Strange created these Monster Men by experimenting on insane asylum inmates, whom he injected with a serum, which wildly overstimulated their growth glands, while inflicting severely reduced intelligence. The resulting specimens were extremely strong, stupid, and dangerous. Strange set them loose in Gotham City, and Batman resorted to extreme measures to end their threat.
This version of the Monster Men Serum takes eighteen hours, from the time of injection, to make the physical metamorphosis. An antidote has been developed, by Batman.
Strange created these Monster Men by experimenting on wealthy citizens that sought medical help in his institution, which was merely a front to cover his illicit activities. Strange developed a "monster serum" that triggered the transformation or normal people into large brutish humanoids, but most were not destructive enough. Batman eventually confronted and defeated a couple of them before going after Strange.
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