Peak Performance Shinobi
Lol I played the more difficult route by not taking out the dude at the side with stealth. Turned out to be one of the most exciting boss fights I'v experienced. 3 ninjas/shinobis battling it out in a small room. I don't play with guides, but I check them out after going through these sections myself for comparison.
The dud is really a tough guy to beat, he is strong and very stubborn . You have to be careful before this dude surprises you with its tactics