Captain Hammer from 'Dr Horrible's Singalong Blog' looks identical to Caleb. They're both misogynists, both violent, and both extremely strong and almost invulnerable. What if this isn't just coincidence?

Hammer is Caleb's identical twin brother. He's been a little more successful at controlling his serial killer tendencies than the evil priest and he channels his violence into beating up 'villains' (especially Dr Horrible). He's managed to convince the public - and maybe even himself - that he's really a hero, although his true vileness is apparent once you get to know him.
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