Suggested by Big Red Steppenwolf is a powerful fighter. He may have been treated as a joke in the old cartoons and comics, he has finally been shown to be a very strong antagonist in the New 52 and in the recent Justice League movie. He has bested powerful opponents like Superman and Wonder Woman in the past (Albeit it with cheap shots) and has enough strength and speed to dispatch most heroes in an instant. However, Thor isn’t like most heroes and has enough power and speed to keep up. At his best Thor may even be faster than Steppenwolf and his hammer will give him the range advantage when trading blows. It’ll be a tough fight, but Thor should be able to snag the win here with his wider arrange of attack options and his edge in stamina. Thor wins.