Sekiro: Shadows Die Twice - Every Ending Explained (And How To Get Them)
6. Immortal Severance - How To Get It
The Immortal Severance ending is a little bit more upbeat, but is probably the most bog-standard 'good' ending there is to get. Essentially, it's just you completing the base mission you set out to accomplish all those hours ago: severing the ties between Kuro and his immortal curse.
All you have to do to unlock this ending is follow the story through and the instructions you're given by Kuro. Say no to the Owl and fight him, and then head to the Fountainhead Palace on the Divine Heir's orders in search of the Divine Dragon. The area itself is one of the most visually inspired in the whole game, as is the fight with the Dragon himself, so you're missing out on some pretty cool content if you take the Shura ending.
After you find and defeat the dragon, you're given its tears. From there you want to head back to the secret entrance down by the Ashina Reservoir, to the field where you fought Genichiro right at the beginning.
After defeating him and the Sword Saint, head over to the bleeding Kuro, select 'Give Divine Dragon's Tears', and watch the ending play out.