Echolocation. The bat can't use its blindsight while deafened.

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

Multiattack. The Void Glider makes one attack with its bite and one with its tail 

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 5 (1d6 + 2) piercing damage.

Tail. Melee Weapon Attack: +4 to hit, reach 10 ft., one target. Hit: 5 (1d6 + 2) slashing damage plus 7 (2d6) lightning damage.

Stunning Screech (1/Day). The Void Glider emits a horrific screech. Each creature within 20 feet of it that can hear it and that isn't a Void Glider must succeed on a DC 13 Constitution saving throw or be stunned until the end of the Void Glider's next turn.