The Revenge of Shinobi

Before you start playing, go to options and set the difficulty to easy. This will give you 9 lives,
and the enemies will be weaker. Then move the cursor over the shurikens and put two zeros. Wait 10 seconds until the zeros turn into an infinity sign. Now you have endless shurikens.
The game itself is not very difficult, but if there are difficult moments or bosses, do not forget that you can save at any time. During the battle with the last boss, there is a mechanism on the right wall that, when hit with a shuriken, stops the press. So, sometimes you need to be distracted from the boss and shoot at the mechanism so as not to crush Naoka.
Here is a video of the passage of the last level 8-2 Labyrinth:
https://www.youtube.com/watch?v=5kysOOu-DKw