Originally Posted by Loki882
Polaris would probably also qualify.
eh... i doubt it. she was souly an X-men character up until recently. That's sorta like saying Mr. Fantastic and Sue Richards can show up in a Avengers film because they're avengers too...
I think the "grey area" is more about what they're associated with more or if it's hard to tell...
the Skrull, Kree, SW and QS are all very arguable in that department. I don't think Polaris is very arguable. She's much much much more heavily rooted in X-men lore than anything else.