The Coinbox is a tower that costs $2000 on medium, and is unlocked at Rank 65. It (side view) looks like a yellow box with pixelated white eyes and a pixelated white mouth. It doesn't attack, but it has 400HP and 5AD. It will also release 2 Bronze Coins per 1HP damage taken. It will still release the coins even if the Coinbox's AD nullifies the damage.