Karthus is top tier now
shield
burn
getting life from burn and damage
increasing burn damage= more healing

no need of boots, just straight run in their team and the work is done
shield
burn
getting life from burn and damage
increasing burn damage= more healing

no need of boots, just straight run in their team and the work is done

too bad it actually costs gold to get those items and almost any midlaner can harass the shit out of Karthus early.
once he has
he can stay in the lane permanantly
this patch doesnt affect karthus much, except that the rylais is much better on him now, if he even cares to build it.
Roa

He will be god Tier ;)
actually no, he doesn't need roa anymore mana and hp nerfed
mana and ap buffed, hp nerfed. and all those items are not more cost-efficient than before, they are just more slot efficient so yes, if you have full build you are stronger now than before, but in a real game, its the same deal. nothing changed about karthus.
wota is troll