Karthus Q buff on PBE
"Lay Waste (Q) damage increased from 40/60/50/100/120 to 50/70/90/110/130"
I mean yeah, it's only 10 damage, but early on in the game that 10 damage could equate to something interesting, especially since Karthus Q deals double damage to isolated targets.
My thoughts are that this is mostly Karthus's compensation for minions being a bit harder to kill now, and they'll be getting more health as well. Though I will say this will also make JG Karthus a bit more interesting since this means he can clear even faster than he could before, which is nice since he's losing the level up mana from Presence of Mind (Precision is Karthus's Go-To Secondary because of both PoM and Last stand, which works while Karthus is in Passive)
It's a Kinda Small buff, but I'll take it for now since I hear Karthus might potentially get some other buffs/changes soon which I hope will also be nice :)