In Ninja you will be scrolling side to side, jumping up and down, and making intelligent use of your power-ups. Your number keys will correspond to the shield, which reduces damage and protects you from death. The falling power-up stops you from falling through the bottom of the screen and the bounce power-up makes you bounce higher. The first stage requires you to grab a key to get to the next stage, and then you'll start fighting bad guys and learning when to use your power-ups to make progress. The background scenes are a nice touch and the music is perfect for this game.