The Ninja Warriors is a single-player, side-scrolling beat ’em up, similar to Shinobi or Bad Dudes Vs. DragonNinja but widescreen format. The player can pick from the strong Ninja, the balanced Kunoichi, or the fast Kamaitachi. Each character is played in a different way and has its own set of moves: a combination of ground attacks, jumping attacks, and throws. They can also assume a defensive posture and charge a power bar that allows them to unleash a blast that attacks all enemies. Various objects can be picked up by the player’s character and used as improvised weapons.
The player will advance through eight levels fighting large numbers of enemies, often being stopped from advancing until all enemies on the screen are defeated. Enemies can approach the player from the left and right sides of the screen and have the ability to move off screen, while the player cannot. At the end of each level, as common in beat ’em up games, the player must defeat a boss. The North American and European versions of the game were censored (changes made to the original Japanese version include removal of the female ninja enemies and replacing them with clawed enemies wearing pink wardrobe, and the removal of the bright green blood entirely when Kunoichi and Kamaitachi attack). The European version, published by Titus Software, is also noticeably slower and easier than the other two. The game was notorious for its high difficulty.
The game is set in a dystopian future United States in the year 2035, where the nation is oppressed by the military of the tyrant president Banglar. The only hope for this broken society is a small underground resistance with plans of assassinating Banglar using three ninja androids. Development of the androids was a lengthy process and the resistance is quickly falling to Banglar's forces, so it has no choice but to dispatch the androids untested.