SRD
Keen Hearing and Smell The Retriever has Advantage on Wisdom (Perception) checks that rely on hearing or smell. Scent Tracking. If the Retriever has a scent of a item or person they can track it for up to 1 mile away, and follow its path within 12 hours.
Bite. Melee Weapon Attack: +1 to hit, reach 5 ft, one target. Hit: 1-2-4 1d4 Piercing damage. If the target is a creature, it must succeed on a DC 11 Strength Check, or be grappled (DC 12 Strength or Dexterity Save to Escape). If the Retriever starts its turn grappling another creature, it automatically hits with the the Bite attack, but the target gets another DC 11 Strength check to escape the Grapple.