Blue Shadow (Shadow of the Ninja in Japan) aims to be a two-player version of Ninja Gaiden, although it plays a little bit differently. Players can either take the role of blue ninja Hayate or red ninja Kaede to defeat the evil Emperor Garuda in the futuristic wasteland of America.

In additional to your standards swords, your ninjas can also wield sickles, which have farther reach but can't hit enemies up close. Shurikens and bombs can also be found in limited quantities, and you can use ninja magic to damage all of the enemies on the screen, at the expensive of some health (hold down the "B" button to activate this)

Unfortunately, most enemies take several hits to kill, which can results in lots of cheap hits if you're not careful. The gameplay is fairly straightforward - although you can't bounce of walls, you can grapple onto certain ceilings and climb on them, which was later borrowed for Ninja Gaiden 3. Despite the ridiculous difficulty of the later sections, it's a fairly decent game with some cool music and decent sound effects