If Your Ninja is Stuck

If you are playing clumsy ninja and your ninja gets stuck on the arena or glitches on an object, the way to reset him is to close the app completely. To do this, return to the Home screen, then double tap the Home button on your device. You will see a list of active apps at the bottom of the screen. Press and hold the Clumsy Ninja icon in this menu and a minus sign will appear in the corner of the app icon. Tap on that to close the app completely.

Don't worry, all your data will be saved, but your ninja will be reset to the center of the arena. On iOS7 you simply need to double tap the Home button, then swipe the screenshot of clumsy Ninja to the top of the screen to close it.