Wow, that updated roster is so sexy! :3
A lot of Helpers/NPCs there! It's just too bad your character can only use a few of them! Maybe have them appear as regular NPCs on some stages (like Speedball) or cutscenes, just so you can see most of them on a playthrough.
About Scarlet Witch, what does she do? Generic attack or like warecus suggested ("random" effect deppending on enemy, like burn, shock, mind control, stun...)? If you could add another one (highly doubt it, too exhausting to add ANOTHER custom pain anim for little gain), you could turn some enemies into medkits, or hp/mp spheres
(BTW, I feel those hp/mp spheres are too rare on later stages! Please add more! ;D )
Great to see Cloak in the game too! Since they always work together, I'm going to suggest you also call Dagger with him (they either teleport in and attack together or she may come first, shoot light beams and then Cloak appears, attacks and teleport them both).
Kitty and Banshee could use their classic costumes colors, instead of regular blue/yellow X-Men uniform. Just a pallete swap would work, I think... (bad and rushly done by yours trully, attached below).
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