This game is quite easy and simple,
all you have to do is write a Pokémon you hate.
The only rule is that you cannot repeat a Pokémon that has already been said.
Whitney´s Mitank, i swear it must got hack with how much it flinch me or getting me paralyze (no i was not aware of the machoke trade until recently nut still)
My mortal ennemie personnally is Exeggcute. I don't even know what I have againts these guys since they're far from the worst design of Gen1. But it's definetly the first I think of when I read people complaining about bad pokemon design.