Aetherworks Marvel probably isn't bannable but its one of the most outrageously un-fun cards in a long time, which says a lot given we have 4 banned cards in Standard right now. I would be surprised if Marvel stopped being a deck.
Hitting any two of card, mana and speed advantage is pretty ridiculous, but Marvel provides all three at a stupidly low cost because WOTC's developers weren't smart enough to notice all of the energy producers they were making around Marvel were simply too good. In a world where 6 energy gives you a repreatable spin of the Marvel, a 3 mana 3/2 with draw a card and 3E is just so far beyond what it should be. The problem isn't even energy itself though, it's Marvel. Everything else that uses Energy is tuned around the real-life play conditions and how much energy you can get, e.g. Harnessed Lightning. It's just that Aetherworks Marvel is priced far too aggressively without any meaningful restrictions, presumably because they're either too dumb to notice how overpowered it is to get a spin of the Marvel or because energy was at one point harder to get.
