User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-6050823-20130604022532/@comment-1837917-20130607035244

@aWC; took your time replying to a dead comment strand there, buddy. Sure, Yian Garuga might not be a 'powerhouse' monster. The term is fan-made. Also, size has nothing to do with it. You went and mentioned Kirin as a potential powerhouse and most of the time those horses are puny. I guess another indicator for a powerhouse monster could be that in later games, they are given extra variations, such as the One-Eyed (or Eared? idk) Garuga, the Golden Rajang and most recently Savage Deviljho.

Taking that into account, sure, Diablos could be one since it gets a One-Horned equivalent with added HP. As I said, there are no strict rules.