From Sonic Retro
|Game: Sonic Unleashed
|Affiliation: Dark Gaia
Dark Bats are generally placed over bottomless pits so that the player can use them to navigate across it grabbing onto them or swinging from them. In the 360/PS3 version, grabbing them will pull Sonic to safe ground or another grabbable object, while they can grab onto one for a ride in the Wii/PS2 version. If the player defeats one, another will appear in its place after a while so they will have another chance to cross.
Dark Bats also appeared as equippable Buddies in Sonic Runners where they were known as a "Green Crystal Monster (L)". Bringing one on a run would turn all crystals green after reaching a specific combo, and its effects were greater when used by Fly Type characters.
|Flocks of these bats make their homes where Dark Gaia's energy runs densest. They aren't particularly hostile, and even if you defeat one, another will soon appear to take up its position.
— Encyclopedia, 360/PS3 version
|You can grab these harmless guys for a ride.
— Art Gallery, Wii/PS2 version