Items, NPCs, quests, objects and spells of patch 1.12.1, read live from the realm itself.

Meaty Bat Wing

NPC	Level	Zone	Chance
Vile Bat Elite	22 - 23	Shadowfang Keep	44.6%
Blood Seeker Elite	23 - 24	Shadowfang Keep	43.5%
Vampiric Duskbat	8 - 9	Tirisfal Glades	40.2%
Greater Duskbat	6 - 7	Tirisfal Glades	39.0%
Ressan the Needler Rare	11	Tirisfal Glades	36.0%