Undead Fortitude. If damage reduces the zombie gnoll to 0 hit points, it must make a Constitution saving throw with a DC of 5 + the damage taken, unless the damage is radiant or from a critical hit. On a success, the zombie gnoll drops to 1 hit point instead.

Rampage. When the zombie gnoll reduces a creature to 0 hit points with a melee attack on its turn, the zombie gnoll can take a bonus action to move up to half its speed and make a bite attack.

Multiattack. The zombie gnoll makes a bite attack and a slam attack.

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 4 (1d4 + 2) piercing damage.

Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage.