Undead Boar

Bloodied Fury. While Bloodied, the boar has Advantage on attack rolls.

Undead Fortitude. If damage reduces the boar 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 boar drops to 1 hit point instead.

Charge. If the boar moves at least 20 feet straight toward a target and then hits it with a tusk attack on the same turn, the target takes an extra 3 (1d6) slashing damage. If the target is a creature, it must succeed on a DC 11 Strength saving throw or be knocked Prone.

Undead Traits. This boar no longer needs to sleep, eat, drink, or breath. It cannot be put to sleep by magical means. 

Multiattack. The undead boar makes two tusk attacks.

Gore. Melee Attack Roll: +4, reach 5 ft. Hit: 4 (1d6 + 1) Piercing damage. If the target is a Medium or smaller creature and the boar moved 20+ feet straight toward it immediately before the hit, the target takes an extra 3 (1d6) Piercing damage and has the Prone condition.