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 7 (2d6) slashing damage. If the target is a creature, it must succeed on a DC 13 Strength saving throw or be knocked prone.

Porcupine Fer. If the boar is hit with a melee weapon attack the attacker takes 3d6 piercing damage as the spiky fer of the boar pierces through the attacker's flesh.

Relentless (Recharges after a Short or Long Rest). If the boar takes 10 damage or less that would reduce it to 0 hit points, it is reduced to 1 hit point instead.

Tusk. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) slashing damage.

Spike Shot. The boar can shake its skin, sending out spikes flying in every direction. Every creature within 10 feet of the boar needs to make a dexterity saving throw DC 14 or take 3d6 piercing damage or half as much on a successful one.

Natural Armor. The boar can use its hard spiked fer to form a natural armor. As a reaction, when the boar is attacked it can give itself a +5 bonus to its AC and gain piercing and slashing resistance for the specific attack. Its Porcupine Fer trait is deactivated for that attack though.