Next up in the Monster Manual is the baluchitherium.  Maybe you didn't know but in addition to dragons and demons and monster of myth in Dungeons and Dragons has always featured a host of prehistoric critters.  There's a whole bunch of dinosaurs coming up in the D's.\


"This creature is a prehistoric anscestor of the rhinioceros.  It is a huge hervivorous mammal with a tendency to charge anything nearby in order to trample it." -AD&D Monster Manual