Upon dying, Karthus enters a spirit form that allows him to continue casting spells for 7 seconds.
Karthus unleashes a delayed blast at a location, dealing damage to nearby enemies.
Karthus creates a passable screen of leeching energy. Any enemy units that walk through the screen have their Movement Speed and Magic Resist reduced for a period.
Karthus passively steals energy from his victims, gaining Mana on each kill. Alternatively, Karthus can surround himself in the souls of his prey, dealing damage to nearby enemies, but quickly draining his own Mana.
After channeling for 3 seconds, Karthus deals damage to all enemy champions.
The harbinger of oblivion, Karthus is an undying spirit whose haunting songs are a prelude to the horror of his nightmarish appearance. The living fear the eternity of undeath, but Karthus sees only beauty and purity in its embrace, a perfect union of life and death. When Karthus emerges from the Shadow Isles, it is to bring the joy of death to mortals, an apostle of the unliving.