Atroxaurus Matriarch

Keen Hearing. The atroxaurus has advantage on Perception (Wisdom) checks that rely on hearing.

Fearless Leader. The matriarch and any member of its tribe within 30 feet have advantage on saving throws against fear.

Charge. If the atroxaurus moves at least 30 feet straight toward a target, it can then do a feet claw attack on top of its multiattack. If it hits, the target takes an extra 16 (3d6+6) piercing damage and must succeed on a DC 18 Strength saving throw or be knocked prone.

Multiattack. The atroxaurus makes two claw attacks and a bite attack or a poison dart attack.

Claw. Melee Weapon Attack: +10 to hit, reach 5 ft., 1 target. Hit: 15 (2d8 + 6) slashing damage and the target is grappled (escape DC 18). Until this grapple ends, the target is restrained, and the atroxaurus can only attack other targets with one claw attack. 

Bite. Melee Weapon Attack: +10 to hit, reach 5 ft., 1 target. Hit: 15 (2d6 + 6) slashing damage.

Poison Dart (recharge 5-6). Ranged Weapon Attack: +6 to hit, range 20/60 ft., 1 target. Hit: 5 (1d4 + 2) piercing damage and the target must make a DC 16 Constitution saving throw, taking 18 (4d8) poison damage on a failed save, or half as much damage on a successful one. Also on a failure, roll 4d6: If the total equals or exceeds the target’s Strength score, that score is reduced to 5 if it was higher than 5. The target is considered poisoned until it manages to succeed on a Constitution saving throw, which it can retry at the end of every turn.

Sweeping Strike. The atroxaurus turns around swiftly, clawing every foe around it. Each creature within 10 feet of the matriarch must succeed on a DC 18 Dexterity saving throw or take 13 (2d6 + 6) slashing damage and be knocked prone.