Rampage. When the hyaenodon reduces a creature to 0 hit points with a melee attack on its turn, the hyaenodon can take a bonus action to move up to half its speed and make a bite attack.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) piercing damage.
Also known as the Giant Hyena, this large stocky carnivore only bears a passing resemblance to the hyena, not actually being related. Like their namesake, hyaenodonts are often bred and tamed by gnoll warbands to be used as attack animals and war mounts.
Desert, plains, savannah, wherever gnolls are found.