Thats a bad mentality to take. Firstly, you're under the impression "a lot of damage" is always a good thing, which is pretty wrong. Second, Ryze raping other champions isn't necessarily a good thing either, because killing other champions doesn't win, knocking towers down does, and Ryze sucks at knocking down towers.
So, in answer, I suggest you find a champion you like. Get good with them, and start helping the team constructively, because if your aim is solely to "rape people" you'll fail badly at the game, and incur a lot of wrath from your teammates.