Bloons TD4 is the newest and greatest Bloons Tower defense game to date (that is, March 2011AD). The goal of Bloons TD is to not allow any Bloons to pass through your monkeys. If they manage to pass through the level, you lose a life. Lose enough lives and you will end up losing the game. Use your mouse to position your monkey towers strategically. Press the button to start the next wave and hope for the best.