You play as an AA gun (!) and have to protect your base.
You play as an AA gun (!) and have to protect your island base from invading airplanes. You should shoot down airplanes by tapping or touching them. Fortunately these airplanes are old and don’t have any guns or bombs, so they have to crush themselves to your island to hit you! And it gives you more time to shoot them down! Note that big airplanes have more health and you have to shot them more than once!