Bat

Bats are flying enemies which can pass through walls and will follow the player as they move about the map. They can pass through both buildings and the ground.

Behavior
When the player first spots them, they will be 'sleeping' on the ceilings of tunnels or buildings. When you open the door to a building or get into its range, it will awaken with a squeak and begin flying around the player just out of normal reach with melee weapons. While not very hard to defeat as one strike from a weapon or bomb destroys them, it doesn't stay still which can be a problem for new players. Also, multiples of these can follow you at once.

Its only attack is to charge in a path at the player, from any angle it may be in relation to them. While it pauses to charge, it leaves itself vulnerable to attacks. The charge can be rolled through, jumped over, or simply walked away from until you get a significant distance from it and it stops following the player. You can swing large or fast weapons to destroy them in their charge path if you get the correct timing.
 * Charging forward