Two buffs that would be nice on karthus
+20 base damage on lay waste at all levels Wall of pain increasing ap ratio and base damage
Edit: It's weird wall of pain is called wall of pain but it does no damage and sucks until rank 3 for slowing.. and even then it still sucks
This way hitting Qs is even more important and missing wall and/or q = big damage loss
Karthus can shit on champions like riven and fizz and trynd, irelia, etc and then get shitted on easily later in the game if his team didn't end it early enough 1v1