- Divorced Installment: The game was initially planned to be a new Tenchu title, but due to the franchise having had many developers and to avoid imitation, the game became a Spiritual Successor instead.
- Dueling Games:
- Fan Nickname:
- Fans have already taken a liking to referring to the game as "Ninja Souls" or "Samurai Souls".
- "LMAO 2Ape" for the rematch against the Guardian Ape where it calls in a second Ape for backup.
- "Voldo" for the Long Arm Centipede enemies, due to their similar fighting styles.
- The Fistful of Ash is often called "pocket sand" after a famous scene from King of the Hill.
- Relationship Voice Actor:
- Throw It In!: The subtitle, Shadows Die Twice, was only meant as a Tag Line for the teaser trailer. Activision would then decide to incorporate it into the final title of the game.
- What Could Have Been: The system for curing Dragonrot-infected NPCs was going to be a bit more involved. Instead of Emma making your first Dragon's Blood Droplet and the Recovery Charm, she was to make actual pills called "Dragonrot Pellets" that would cure it. Said pills were also supposed to be made via spending Wolf's Resurrective Power and given to the infected in-person, rather than praying with the Charm at a Sculptor's Statue. The mechanic was changed late enough that there's still dialogue strings for it in the game's code, although the item itself isn't there.
- Working Title: During development it was simply known as "Project Ninja."
Trivia / Sekiro: Shadows Die Twice