Press Start To Begin. Use the Arrow Keys, WASD (On QWERTY keyboards) and ZQSD (On AZERTY keyboards). Throw a ninja star into the correct target to advance to the next level.
You have INFINITE lives, so the boss should be pretty easy. Stammer: http://scratch.mit.edu/projects/16460347/ Stammer 2: http://scratch.mit.edu/projects/16546896/ Stammer 3: http://scratch.mit.edu/projects/18663789/ Stammer Brothers: http://scratch.mit.edu/projects/22300312/