Bats are enemies that appear in every Shantae game.
In Shantae, they are adorable purple bats with white horns and wings. In Risky's Revenge, its wings are red, and they add a tiara and a horn in the middle of its head. In Half-Genie Hero, its horns are bigger and its eyes are red, but the middle horn is removed.
They are still until Shantae gets close to them. Then, they move towards her and attack. Their movements are slow, and they aren't very agressive. In Pirate's Curse, they have 1 HP, and when killed they explode in blood.
It's a proposed form for Shantae in Half-Genie Hero. You could see in the dark using its sonar.