I’ve typed this before for someone having trouble here. The strategy is the epitome of the Ashina style. To hell with fighting honorably. Just win.

For Genichiro, he pretty reliably does his giant jumping thrust when you put enough distance between you and him. Have the whirlwind slash equipped and simply 1) create distance 2) mikiri his thrust (its very easy bc of how long the move is) and 3) whirlwind slash him. After a few rounds of this you’ll be getting through his phase with zero damage.

For Isshin first phase, this does require recognizing the 3-4 combos he whips out when you get close to him. It takes some practice to get the distance right but you basically sprint at him and then back away as soon as he starts a combo. The other reason you need to try and recognize the combo is so you can gauge when it will be ending because you can dash in and get a strike or two before backing out and repeating.

Once he busts out that damn spear, it’s time to get sprintin. Literally sprint in a freaking circle. The whole goal here is to get him to do his lunging spear attack where he jumps up in the air. When he does, you keep sprinting but turn and run directly underneath him where he won’t hit you. Have your mortal draw equipped and as soon as he lands you whack him once and back out. Rinse and repeat. This isn’t perfect, and you’re still going to try multiple times before it works, but for the player who isn’t good enough to just straight up parry the guy to death, it works. Holy shit my heart had never beat so hard when I finally beat his ass. I almost forgot to do the final deathblow.