Echolocation. The bat can’t use its blindsight while deafened.
Keen Hearing. The bat has advantage on Perception checks that rely on hearing.
Maneuvers. The bat uses maneuvers (maneuver save DC 11). It has 2 stamina dice which are d8s, a dice limit of 1, regains all expended stamina dice when it finishes a long rest and regains half its total stamina dice when it finishes a short rest, and knows the following maneuvers:
Bite. Melee Weapon Attack: +0 to hit, reach 1.5 m. Hit: 1 piercing damage.