REVENGE OF SHINOBI 
Extra Life 
On the first level, enter the second building and find 2 spikes near each other. Use the "ninjitsu of mikin". An extra life will appear between the spikes. 
Submitted by Dexter Whisman (lonaelbert@aol.com) 
Special Bonus 
Finish any level with enough shurikens to equal 11 times the number of lives remaining, and you will receive 30,000 bonus points (i.e., if you have 7 lives left, finish the round with exactly 77 shurikens.) 
Unlimited Men 
In round 4-2, there are many power-ups hidden that are revealed only by shooting them. On the first platform, jump and shoot and you'll reveal a 2-up on the platform across your position. Get it, die, and repeat! There's another 2-up on level 3-2. Go to the second elevator and locate the crates that are in the middle of the screen (on the second level). Then shoot the bottom-left crate until the 2-up appears. 

Unlimited Shurikens 
For unlimited shurikens, set the number of shurikens on the Options screen to 0 and wait about 20 seconds. The zero will turn into an infinity symbol, giving you an unlimited number of shurikens. 

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