What exactly shuts down the new Warwick?

I just played him for the first time and he honestly feels broken once the snowball starts. His q heals wayyyyyy to much mid game. I literally 1v5'ed in the enemy base (My penta got stolen as I was chasing it down D; lol) Mind you this is at low elo, but I feel like he's either freelo at the moment or the new bronzezodia god. My build was Anyway, happy hunting and may the climb be ever in your favor summoners