Isshin, the Sword Saint - Full Fight - First Playthrough
It took me about 3 hours before finally beating this boss.
Tips
The first battle is with Genichiro, the Way of Tomoe. He is quite easy once you get the hang of his patterns.
The real fight begins when Isshin appears. For the first phase, he uses some quick samurai moves. Do your parry thing. Run away when he uses the windy sword techniques. Run fast towards him after that to get some hits.
The second phase is quite challenging. He gets a really long spear and he has a gun. The range of the spear is crazy and he does some crazy unstoppable combos. Always be running and blocking and parrying his attacks. I wait for the thrust attack so I can do the mikiri counter.
The third phase, he has the same set of moves with some additional lightning attack. Just do the hit and run technique. It will take some time but it will get you there for the win.
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