Crushing them with his tail, doing more nommy, til legendary pokemon brother him too much, so he use his extra strong water gun to get rib of some of them, some earthquake with his big size to crush more of them and then then rising a huge wave of muddy water to finish them all off!
After that final attack though he kinda wonder where did everything go around it, a bit unaware of the amount of damage he caused, and just walk off to another continent~