Keen Hearing and Smell. The hound has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Pack Tactics. The hound has advantage on an attack roll against a creature if at least one of the hound's allies is within 5 feet of the creature and the ally isn't incapacitated.

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) piercing damage plus 7 (2d6) acid damage.

Acid Breath (Recharge 5–6). The hound spits acid in a 5 by 30-foot line. Each creature in that area must make a DC 12 Dexterity saving throw, taking 21 (6d6) acid damage on a failed save, or half as much damage on a successful one.