5) Crime Syndicate Of America
Who could pose a bigger threat to the Justice League than a union of their greatest enemies? How about a team of their evil doppelgangers from another Earth? Yep, that’d do it.
Hailing from Earth-3, the Crime Syndicate of America (or CSA) is made up of twisted analogues of Earth-1’s heroes – Ultraman (Superman), Superwoman (Wonder Woman), Owlman (Batman), Johnny Quick (The Flash) and Power Ring (Green Lantern). Other members include Grid (Cyborg), Sea King (Aquaman, duh), Deathstorm (Firestorm) and Atomica (Atom). Psychopathic, violent and rotten to the core, the CSA are the exact opposite of the Justice League but with all their powers. Which makes them a far greater threat than most.
The team are a popular one for adaptations and have featured – though usually with a different name – in TV series like Super Friends, Justice League and Batman: The Brave and the Bold and animated movies like Justice League: Crisis on Two Earths. Ultraman also appeared in a couple of episodes of Smallville.