A Bunny is a harmless creature that spawns in the daytime. It cannot deal damage to the player, and the player cannot deal damage to the bunny.
The bunny has 5hp by default, but if vile powder is used on a bunny, or it is night time and a Blood Moon is out, it becomes a Corrupt Bunny. A Corrupt Bunny is capable of doing damage to the player, and the Player may damage the Corrupt Bunny.
The bunny will hop around aimlessly during the daytime, and stay in one place looking from side to side when night falls. They cannot open or close doors. They cannot be killed by the player, Falling Stars, Sand, or Explosions. A hostile NPC is capable of killing them though. A corrupt bunny may also kill a regular bunny. Vile powder can be used on multiple bunnies at the same time, if they are in range of the powder. A bunny tends to de-spawn very quickly.