Bishop vs. Apocalypse - Marvel Champions Gameplay 

So you are getting the obligation on the villain phase, not yours. But past that, an obligation changes your hero with an ability action (appendix 3 explains the first line of the obligation is an ability). So under pullet point 3 of form, change form it states: If a card ability causes a player to change forms, it does not count against the one voluntary form change the player is permitted during their turn that round. Since the card ability is changing your form, it doesn't count against your voluntary form change that you're allowed to do. Hopefully that explains it well enough! His obligation is also very weak, others are a bit tougher to deal with.

Awesome! That helps so much! Thank you!