Shadow Warriors (or Ninja Gaiden in non-PAL countries) is a coin-op created by Tecmo and released in 1988. The home computer versions were developed by Ocean and published in 1990 for the Amiga, Atari ST, Commodore 64, Amstrad CPC, and other platforms. The NES version was created internally at Tecmo.
There are a few differences between the NES and other versions because the NES Ninja Gaiden has several platforming elements. In contrast, the Ocean version resembles progressive beat-em-ups such as Double Dragon. Said that we are talking about one of the most famous arcades of the 80s and a great game that can be played by two simultaneous players in co-op mode.