Ending 1: Shura
After obtaining both the Shelter Stone and the Lotus of the Palace, all of the Sculptor's Idols in the Ashina Castle will become inaccessible. Upon reaching the top of the castle, Owl will be waiting on the rooftop, presenting Wolf the choice to obey the Iron Code or to stand by Kuro. Choosing the former is required for this ending.
Then, Wolf will have to fight two bosses exclusive to this ending back to back: Emma, the Gentle Blade and Isshin Ashina.
After the boss fight, Wolf will murder Owl and become Shura, marking the beginning of the most tragic massacre of the Sengoku era.