Ankylocodon

Vulnerability Resistance. The Ankylocodon has advantage on saving throws against being incapacitated, having its speed decreased, and against effects that would make it take extra damage. 

Multiattack. The ankylocodon makes three melee attacks. If both attacks hit different targets, those targets must succeed on a DC 13 Constitution saving throw or have their number in the initiative order decreased by 1 until the end of the next round.

Tail. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) bludgeoning damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked prone.

Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 18 (4d6 + 4) piercing damage.

Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (1d12 + 4) slashing damage.