Had a legal question

Please do not even answer if you are unsure.

But anyways me and a buddy were talking about copyrights and the question came up.

"In a game like league of legends where entire character concepts and abilities can out of the blue be completely changed are the old abilities/ concepts still copy righted?"

I say that they probably would be but his argument was

In a game like say street fighter in one game a character might have certain moves but in the next released street fighter he may get tweaks but you can always go back and play the older games. In league once a character is reworked you cant visit older patches a change deletes the old and replaces it makin it no longer exist. So why would copyright still be in place.

Cant find any real answer online. Wondering if anyone knows the answer.