Rhinoceros

An armored grey behemoth with a horn like a battering ram and a temper to match, charging anything that startles it with bone-shattering force. Its hide turns aside all but the heaviest blows.

Horn Gore: piercing, melee 5 ft, +1 to hit, 3d8+5 piercing. Devastating Charge: after moving at least 20 ft it gores for an extra 3d6 and the target is knocked prone and thrown 10 ft on a failed Dex Quick save, cooldown 3 rounds.

Armored Hide: thick skin turns aside lesser blows and it resists being held or moved. Poor Eyesight: it charges the first thing that moves and has -2 to notice still or distant targets. Senses: Twilight Sight, Keen Smell.