Which Pokémon would genuinely surprise you that it’s not the ace of a gym leader/Elite Four member/champion?

Like, I've always really liked Nidoking, and I've always wondered why it wasn't Giovanni's ace Pokémon, considering it's a Ground-type Pokémon with "king" in its name, something that, in my opinion, would suit the last gym leader who is also the leader of a mafia. Not to mention that Nidoking had a unique typing at the time (Ground/Poison), which I feel fits very well with the leader of a villainous team.