You control "The fighter" and shoot down a UFO. The UFO appears from the left. When the UFO arrives at the right-side end, the UFO go to the left, and the UFO approaches. When there is a UFO to the left than a fighter, You hear a sound from the left speaker. When there is a UFO to the right than a fighter, You hear a sound from a right speaker. When You are in right above, You push the space key, and please shoot it down with a laser. "The fighter" moves with right and left key. The UFO may appear from the right. Plural UFO may appear. When a UFO goes down to the bottom, "The fighter" is destroyed. The UFO shoots a missile. When "The fighter" crashes into a missile, it is destroyed. [The fighter] is three planes. You can make a barrier for two seconds when You push the Z key. The barrier can prevent a missile.