The best ninja game ever released.
I played it again on an emulator not too long ago, and it still shines. The animations were surprisingly slick, and the environments were amazing for a Sega console game, and most important of all, it was a hell of a lot of fun, regardless of how long it takes to beat it.
To this day, I have no idea what the story of this game is about, it starts out in the woods, killing assassins and giant samurais, and slowly winds into this crazy mech killing, surfboard riding super soldier killing plot. As you can tell, it's highly Japanese.
The Music, Sound and Graphics were very impressive at the time, I can still remember songs played and every sound effect from the game.
I rate this game 9, I would recommend it if you're going to emulate old sega games, or have a lot of spare time.