Tips for playing as the champion Karthus
◊ Ask your allies to help point out when you should use Requiem to get kills in different lanes.
◊ Lay Waste is very strong at farming minions and harassing enemy champions.
Tips for playing against the champion Karthus
◊ Karthus can cast spells for a short duration after he is killed. Move away from his corpse to be safe.
◊ Make sure you always have enough health to survive Requiem, even if you have to go back to the base more frequently to heal.