(Innate): Upon dying, Karthus enters a spirit form, which allows him to continue casting spells for 7 seconds. During this time, his abilities cost no mana.
Ability
Description
Leveling up
Lay Waste
(Active): After a 0.5 second delay, Karthus blasts target area at the cursor's position, dealing magic damage to every enemy in the area. The damage is doubled if it only hits one unit.
(Active): Karthus creates a wall between 2 obelisks at target position for 5 seconds. Enemies who pass this wall have their armor, magic resistance, and movement speed reduced for 5 seconds.