Tauros (Japanese: ケンタロス Kentauros) is a Normal-type Pokémon introduced in Generation I.
It is not known to evolve into or from any other Pokémon, but it is considered to be a counterpart of Miltank.
Obviously, don't nominate any human characters. Hybrids like Cheetah or The Lizard are okay, as are shapeshifters with one set animal form (eg Professor McGonagall.)
