The Cave Bat is a common type of Bat found only in the Cavern layer. They are fairly small, and can be difficult to hit with certain weapons. One is to proceed with caution when entering caves early on, as the Cave Bat can pose a moderate threat when one is not prepared to deal with them. If a world is in Expert Mode, they can inflict the Feral BiteDebuff and deal more damage, making them more dangerous than those on a normal world. Like most other bats, they cannot enter water.
Once a world enters Hardmode, Cave Bats will be mostly overrun by Giant Bats, making them a bit less common than they were pre-Hardmode.
Cave Bats, as well as Jungle Bats, Hellbats, and Spore Bats have an unused frame in the animation that seems to depict a Cave Bat hanging upside down. This may mean that bats were originally planned to be able to hang on ceilings but was later decided against.
Players can easily farm for the Cave Bat's item drops if they have a Bat Statue. The bats spawned won't drop any coins, but they will still drop items if summoned with the statue, as long as they are not killed by lava or traps.
The Bestiary entry for the Cave Bat: "They are small, hard to see, and swiftly flap about in unpredictable ways. They often carry diseases, such as rabies."