This guide has not yet been updated for the current season. Please keep this in mind while reading. You can see the most recently updated guides on the browse guides page
Your votes and comments encourage our guide authors to continue
creating helpful guides for the League of Legends community.
Don't get that get in your way, I have almost played only Karthus all the way from level 1 to 30, and I have well over 200 games with him. He is in my opinion, one of the best champions in the game.
Simple to start off:
Press R to win.
Requiem is one of the best ultimates in the game, hands down. It's a massive global (kill securing). At full build, it does over 5000 total damage. And it can not be interrupted once Karthus is in his passive.