I like the game but I think the bat swing should be automatic, something like press the attack button and then spin around, otherwise, I as a player I will just spin the mouse's cursor a get the same effect. And I found a bug in the 3rd level, after being hurt by an explosion, I lost the hat and was behind a wall, unreachable.
Also, I think you should try to make the enemies attack more visually readable, many times I got hit and I was like "Hey, what hit me".
Good demo, it have potential, cute character too, I will not be surprised if the game sell just because of the violent bunny. Keep up the good work.