Sekiro™: Shadows Die Twice – Guardian Ape Immortality Severed Achievement & Trophy Guide
Used the Mortal Blade to sever the Guardian Ape’s undying
After beating Snake Eyes in the Ashina Depths, continuing further down will offer you a chance to kill the Guardian Ape once again. The exact same move-set from his headless form will be present here. You will not have to worry about feces flings or poisonous flatulence. Just his fear shriek.
For this fight, you won’t be able to cheese his dive ability like you did the last Guardian Ape fight. The arena is much too small. This time, you’ll want to stick close to him and grab opportunities to slice in between his shrieks. This is by far the best method.
Second Iteration
Once you get the first deathblow down, he’ll summon another ape to come down and fight. This is a lot easier than it actually sounds. Equip your fireworks prosthetic and use this against the secondary ape. You’ll find their stagger bar goes up considerably. It took me about twenty seconds to kill.
Then you’ll go back to fighting the Guardian Ape just like you did before! Once you deliver the final deathblow to him, you’ll want to slice his corpse a few times to allow a third deathblow on the insect that was controlling him.
You’ll go into an animation with the mortal blade and execute them for the achievement.