The Balloon is an enemy which only appears in Hardcore mode. It has a balloon tied to its back which makes it fly, making it immune to collision damage, as well as making it undetectable by most ground towers and units. The balloon on its back pops when the Balloon loses all of its shield health, making the enemy vulnerable to collisions and ground towers. The Balloon can be spawned by the Grave Digger in Hardcore mode. The Balloon can also be spawned from the Mystery upon its death in...