it depends on how you play. try this out and see what you think (i love this set up)
Fist Energy + Sorcery + Wonder Woman (make sure your movement is either Acrobatic or flying). When you have access to ICON POWERS (level 12), get Shazam. Focus on getting your Power and Might as high as possible with your equipment. When you have access to acrobatic attacks, get the attack that ropes an enemy and pulls him in. Use the sorcery spell that does this as well. Do one, then the next, then hit a heavy strike combo, and they are dead.
Shazam, for me, dealt 1000+ damage when I was level 17 with this set up in mind, and it heals you of damage (keep in mind it has a wait gauge). In other words, it was an instant kill. Hence why I mentioned it.
Other great combos are Earth (or whatever) combined with Superman and any ranged weapon (dual guns is epic for this). Movement wise, choose acrobatic (you get the ability to fly and run fast from 2 of your transformations from earth). If you don't want to use guns, brawler is deadly with this combo too (as is martial arts).
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