I'll be honest, I really don't know how to feel about this game. On one hand it's a cool NES platformer, but on the other hand, I don't think it lives up to the essence of the first two Ninja Gaiden games.
Be that as it may, let's talk about the things and additions that I did like, starting with the graphics which are amazing most of the time, even at times almost looking like this is a 16-bit game, and that's great since I think there's almost no lag in the game. The music is also good, but there are only like 4 songs for all the levels, which is very disappointing. Also, it feels like the Ninja Gaiden formula is more polished than ever, as you can now hang onto platforms from below, which is a nice addition. The lamps show what item you'll get now, and the story is even more interesting as well, or at least unfolds better in my opinion.
Moving on to the bad part of the game... let's start with the most obvious, and that is that that frenetic pace that so characterized the first two games is gone, instead now Ryu feels " sluggish" and while it doesn't automatically make this a bad game, to me the new pace is not cohesive with the one established in the previous games, it feels straight up like a step backwards that was only implemented to make the experience more casual, but for the worse. On the other hand, the level design and enemy positioning is less challenging, which might seem like a positive thing given that the game is now more accessible and bearable, however, that's taking away a lot of the Ninja Gaiden essence of this game, as all but the last level are too easy.
Aside from the above, this is more of a personal opinion, but I'm really not a fan of the fact that they changed the ninjas and demons as enemies for robots and biological experiments, I mean, that has nothing to do with the previous games, how on earth were they able to change the iconic death eagles for a generic robot with wings, and the story although I thought it was good, it has nothing to do with the tone of the stories of the other 2 games. This one seems more like a Contra or Mega Man game with a Ninja as the main character instead of being a Ninja game as such. I don't dislike it, but it's not cohesive with what was presented in the previous games, not to mention it makes the game feel less unique.
Conclusion
Yes, you'll definitely come across one of the most polished platformers out there for the NES, it's a very good game and you can finally finish it without save states, but even so, I feel like it feels more like a downgrade to the gameplay and setting than anything else.
Be that as it may, let's talk about the things and additions that I did like, starting with the graphics which are amazing most of the time, even at times almost looking like this is a 16-bit game, and that's great since I think there's almost no lag in the game. The music is also good, but there are only like 4 songs for all the levels, which is very disappointing. Also, it feels like the Ninja Gaiden formula is more polished than ever, as you can now hang onto platforms from below, which is a nice addition. The lamps show what item you'll get now, and the story is even more interesting as well, or at least unfolds better in my opinion.
Moving on to the bad part of the game... let's start with the most obvious, and that is that that frenetic pace that so characterized the first two games is gone, instead now Ryu feels " sluggish" and while it doesn't automatically make this a bad game, to me the new pace is not cohesive with the one established in the previous games, it feels straight up like a step backwards that was only implemented to make the experience more casual, but for the worse. On the other hand, the level design and enemy positioning is less challenging, which might seem like a positive thing given that the game is now more accessible and bearable, however, that's taking away a lot of the Ninja Gaiden essence of this game, as all but the last level are too easy.
Aside from the above, this is more of a personal opinion, but I'm really not a fan of the fact that they changed the ninjas and demons as enemies for robots and biological experiments, I mean, that has nothing to do with the previous games, how on earth were they able to change the iconic death eagles for a generic robot with wings, and the story although I thought it was good, it has nothing to do with the tone of the stories of the other 2 games. This one seems more like a Contra or Mega Man game with a Ninja as the main character instead of being a Ninja game as such. I don't dislike it, but it's not cohesive with what was presented in the previous games, not to mention it makes the game feel less unique.
Conclusion
Yes, you'll definitely come across one of the most polished platformers out there for the NES, it's a very good game and you can finally finish it without save states, but even so, I feel like it feels more like a downgrade to the gameplay and setting than anything else.