There was a time Iron Man was a dude in a clunky metal can with some over muscled magnets, that also made him pretty strong, but whose battery was constantly running out. Since then, he's had armors that hide inside his bones, and armors made out of nanites.
Weird things used to happen around The Scarlet Witch if she was careless about pointing at people or things, and she could only do her trick two or three times in a given - unspecified - period. Then she started remaking reality to suit her fits of pique.
Clearly, some of Marvel's finest have undergone big changes. I'm interested in the other guys.
Whose abilities have been the most consistent, or changed the least from their introduction until today? (both sides of the hero/villain divide are welcome)