THE BASIC PRINCIPLES OF QUALITY DICE

A jerk DM could claim "identical creature" to some horse just isn't essentially granted to every thing using a quad of equine legs, the humanoid torso disrupting the "similarity" so zerbra's and unicorns yes, centaurs no.  But that's a jerk DM.   Mobility will not be a challenge if he is applying melee, he'll have to spend ki or deal with attac