Nioh and Nioh 2 (including all DLCs) are also bundled in the Nioh Collection on PS5.
The Dojo Mission Zen and the Sword are One pits William against Yagyu Sekishusai, a master of the Katana.
Dojo Mission – Zen and the Sword are One Walkthrough
Main article: Yagyu Sekishusai Boss Guide
While extremely quick to counter you, Yagyu Sekishusai does give you some opportunities to strike him. Pay attention when he does his sword slash that causes him to step forward, you can dodge to his side and retaliate. Avoid attacking him first, as he is very agile and will not let any opportunity to strike you pass.