Sega Genesis :: Shinobi III - Return of the Ninja Master Cheat Codes
Bonus PointsHere is a handy hint to boost your score. Go through the hold stage without using your shurikens. If you manage this feat then you will be rewarded with 30,000 points in your Shinobi Bonus. I have been told you get a 50,000 points for not using your sword but I haven't pulled that one off yet.
Invincibility
At the title screen, choose Options. In the Options menu, move down to the "S.E." command and use the B button to play these songs in order: "He Runs," "Japonesque," "Shinobi Walk," "Sakura," and "Getufu." Exit the Options screen and start your game. You are now invincible!
Unlimited Shurikens
At the Options screen, set SHURIKENS to 0, then set SOUNDS to "Shuriken". Highlight SHURIKENS again and the 0 will change into an infinity symbol.
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Tips:
stage I while hanging in the rope try to jump and you will see a secret entry. also in the next rope
Stage III Body weapon: at the last stage at the second safe pointwhere the monster hide stop targeting youjump up in the white line above.