Player one is automatically assigned the red female ninja, and player two the blue male one. Even though the game includes a DIP switch that allows you to choose ninjas at the beginning of a game, there's no difference between them at all.
Ninja Warriors plays exactly like "Kung Fu Master", but what really disappoints is the lack of varied moves compared to other beat'em ups of the time like Irem's "Vigilante". Besides commands like jump, kneel, block, and shuriken throw; the melee attack is always the same whether you are kneeling, standing or jumping. In fact, because of this, the mid-air hit isn't your typical flying kick, but a totally useless horizontal kunai slice.
The characters' movement is too slow and robot-like for its own good, not mentioning they walk like dorks. As a result, the ninja characteristics that define them (think "martial artist", "quick" and "acrobatic") are totally absent.
Movement is limited to only left or right, and enemies go down with only one hit or 2 shurikens.
Most of the game involves rapidly turning left and right to dispatch regular enemies, but bosses' and minibosses' computer-perfect reactions were shamelessly designed to eat thru your change and leave you bankrupt. That's if you are still playing after 10 minutes.

The game had problems making itself known right from the start. Ninja Warriors ran on improved "Darius" hardware, called the "The Ninja Warriors" board (which would also later house "Darius 2"). As such, the game demanded a dedicated cabinet with 3 monitors lined up for a total resolution of 864x224 (288x224 each monitor), giving a very long horizontal display. Awesome? Yes. But also a lot more expensive than your average filthy and cigarette-tattooed recyclabe cabinet. Small arcade owners thought twice about including the game in their locations, leading other titles in the genre like Taito's mediocre "Superman" to be more popular among players.
On the other side though, the strange resolution allowed for NeoGeo-like HUGE sprites. Characters and enemies have surprisingly fluid animation, and the main characters lose their skin and clothes as they take damage on their limbs, revealing their cyborg nature.

Having 3 screens also emphasized the need for beautiful and very detailed levels, and Taito delivered. Few times plain, but overall gorgeous stages for the time. With graphics rarely repeating themselves. The Air Force base stands out the most.
Effects like squirting blood and specially big explosions look amazing even for today's 2D standards.

The sound effects are quite good, and some digitized voices and screams can be heard during play. You can also hear a robotic voice sample play during the first stage's very catchy song that adds to the overall anime/techno theme of the tune. This same voice reads out loud your initials when entering a high-score.

Ninja Warriors was definitely more successful on the different home computers of the time, and even Mega-CD and PC-Engine. Its main attraction, the extra-wide view, would have to be scaled down a bit at the cost of smaller sprites. While the Atari-ST, Commodore 64 and Amiga versions adopted this option; the Amstrad's, Spectrum's, Mega-CD's and PC-Engine's ended up with almost regular-sized screens but bigger sprites. Make sure you try these last two ports after the arcade is done depleting your patience. Both feature slightly improved gameplay and ninja selection. Also, the PC-Engine's adds various color choices for your ninjas and plays at a higher speed; while the Mega-CD's has both original and arranged soundtracks and a nice full voice narrated intro.
For those of you who are familiar with Taito's sound team "Zuntata", Sega's version also includes a very strange and disturbing cinematic prologue (that oddly has absolutely nothing to do with the game) played out by them. By cinematic, I mean grainy, 16 colors slideshow with voice acting. And when I say disturbing, I mean that it's presented as a cheesy "film noir". Yes. A "film noir" with a japanese detective roaming japanese streets, in search of a flamboyant music band. Not to be missed. Hey, at least I do like their music.

A technical curiosity more than anything, the original Ninja Warriors turns boring and frustrating very quickly despite its great looking graphics and good sound. Make sure you check out what its awesome hardware could do at the time, but I'm warning you, the gameplay isn't there.

Soundtrack:
	Level 1 (Mega-CD Arrange)
	Level 2 (Mega-CD Arrange)