If you’re a fan of the defense genre of gaming, you may want to check out Defender from DroidHen. It was recently released into the Android Market for the unbeatable price of free. The goal of the game is to defend your castle against endless waves of enemies. Every ten waves, you will encounter a boss battle, which can vary from challenging to sometimes impossible. In order to stay competitive, you will need to continuously upgrade your crossbow, magic (fire, ice, lightning), defense and other skills as you progress in the game. Check out our review of Defender in the video above, then hit up the Android Market to grab your free copy.