Well given the context you probably wouldn't be able to play a predator... predators would probably be monsters only... then again some versions allows you to play monstruous adventurers...Well... I really only wanted to make a bear that was made of lava... but now I want whatever that monstrosity was.
Anyway! Depending on you class you could totally end up turning permanently into lava, you'd need to level up, it would possibly be a last level reward but you could do it! And before that you could get some temporary tranformations. I can think of at least one way of getting that result in Pathfinder using the regular rules and depending on how much we homebrew it there could be others.