Alter egos with the genius trait: Hulk, Spider-Man, Ironheart, Iron Man, Rocket Raccoon and Wasp.
Heroes with the Champion trait: Ironheart, Nova, Spider-Man and Ms. Marvel.
I really like Moon Girl, but it needs a specific deck to work. I use it in a green spidey (Peter) deck and works super well. If you pay with three cards in your hands basically you are playing her for free because you are drawing the same number of cards. But sometimes you can use things like Peter´s ability, Ingenuity or Quincarrier to maximize the benefit, drawing more cards that the ones you are spending. 2 thw and a block or 4 thw is not bad but you are only using Moon Girl if you can trigger her drawing effect. The only problem is when you draw her in a turn that you don´t want to go to ae and you are using someone like Peter but anyway I think she is a great ally in some decks.