If you're looking for a ninja game keep looking. This game is along the same lines as the Rastan Saga series only MUCH worse. The control is lacking, and the over all game experience leaves you wishing you could take the game back to where you purchased it. I recommend looking for Ninja Spirit, or Ninja Gaiden -- you'll be much happier.
This reminds me of Kenseiden on Master System, but it isn't anywhere in the same ballpark gameplay-wise.
Not much to add, other than avoiding this game if you tend to play VGs for mere enjoyment in the first place. I completed it once, bound and determined to get my moneys worth ($2.50). Only problem is, I didnt- and had blown roughly 2 1/2 hours of my life in the process. Hideous grafics, laughable character design, crap controls, and horrible music round out this sad excuse for entertainment. Any other Ninja/ Samurai-themed game out there would most likely be your better choice.
First off I'll say it's better than the first one- and secondly when you play it you WANT to love it- but something holds it back from being great- obviously it's the chocky playability. Everything else is great- to me anyway- though it is too hard.