You see Bat
"Flap! Flap!".
Notes
Usually found in large groups. It seems to be much harder to get bat wings after the Winter Update 2008
Abilities
Melee (0-8)
Damage Taken From Elements
Physical 
Death
Holy
Ice
Fire
Energy
Earth
Location
Dark Cathedral, Tiquanda, Mount Sternum, Folda, Minotaur Camp underground, Kazordoon, Femor Hills, Bat Cave south of Thais (introduced in the Summer Update 2008) and in most other caves.
Behaviour
A bat will retreat at 3 (10%, red) health.
Strategy
Just attack them. They are a bit stronger than rats.