Nioh and Nioh 2 (including all DLCs) are also bundled in the Nioh Collection on PS5.
Okatsu Boss Guide
William encounters the ‘kunoichi’ Okatsu inside a fighting dojo during the The Defiled Castle Main Mission.
Her main arsenal are light but weak attacks. When the battle begins, wait for her to deliver a combo, evade it then stab her with a spear with the mid stance. Use ▲ to deal some heavy attacks, this performs very well when she’s cornered, eventually her guard will wear out. When you get her to fall, perform a finisher to deal even more damage. The recommended equipment for this battle are light weight armor, best paired with the Guardian Spirit Kato to replenish Ki whenever you need it. She occasionally does a backflip and follows up with projectiles or a 2 combo air dash, thus keep an eye out and constantly strafe then time and dodge to the side.
In addition, she is vulnerable to the high-stance Spearfall skill, this causes her to topple over. One of the best opportunities to use this is whenever she is about to finish summoning. Connect the finisher. A good signal for when she becomes prone to attacks is when she glows yellow, thus it’s best to move quickly and deliver as much damage as you possibly can.