One champion is still reigning supreme in League of Legends when it comes to dealing damage.
Karthus tops the leaderboard of most avege damage dealt in every nk in League, according to stat site U.GG. Furthermore, he does so in multiple positions. In most nks, he takes the No. 1 spot as the jungler. But in some, he claims it as an AD carry champion, like in Gndmaster and Diamond.