The Hook Bat's body is small and oval-shaped; short ears sprout out of the top of its head. Its eyes are small and glow yellow; its Heartless emblem is on its chest. Its mouth is jagged, and its large wings are attached to either of its sides, each sporting a silver spike close to the Heartless's head. The Hook Bat's body is blue, except for the tips of its ears and wings, which are navy blue. A short, silver chain connects the Heartless's body to a large, red hook with a yellow base.
In Kingdom Hearts II Final Mix, the Hook Bat is predominantly dark red, with black-tipped wings and a silver hook.
The Hook Bat's name references the fact that it resembles a real-world bat, as well as the hook attached to its body.
The Hook Bat has little HP and is easily defeated by air combos, though it may evade Sora's strikes by flying. They are easily defeated by Magnet magic followed by another attack or basic cast of magic such as Thunder once they have been gathered.
Hook Bats normally fly around in the air, occasionally descending to use their Hook Somersault attack. If damaged, they will retaliate with Ultrasonic Attack. Their counterattack is more powerful and cannot be blocked, so it is recommended to avoid any interruptions when combo attacking them.
Using the Bat Cry Reaction Command allows Sora to grapple the hook on Hook Bat and swing wildly, damaging all foes in range. Hook Bats generally appear in swarms rather than alone, making it easier to swiftly transition from one Reaction Command to another. As such, when Hook Bats appear alongside other enemies it may be advantageous to defeat Hook Bats last in order to deal more damage to surrounding enemies by getting more use out of the Bat Cry Reaction Command.