Hi Peppoah,
His damage output is somehow "low" nowadays, idk why. But i use him as a lifesaver more than damage dealer when i am facing a tough team at PVP. I put 4 x Strength + 2 Yellow Will (I will put Immunity Will when i max them) for more survivability. Even he doesn't hit so hard, at least hits around 2000-3000 k AOE damage at the same time with healing with a chance to get an Extra Turn with power move.
If you don't get first turn on PVP, on second turn he literally can save your life.