AI: The Somnium Files - Nirvana Initiative: Nil Number And Secret Ending Guide
The nil number is the key to AI Nirvana's secret ending.
AI: The Somnium Files - Nirvana Initiative has many endings, including a "secret ending" that can only be unlocked with the Nil Number. It's not an ending included in the flow chart, but one that appears off to the side--almost like it wasn't supposed to exist. So, what is the nil number and where can you find it?
It's a six-digit number that Tokiko asks for if you tell her you're a Frayer in Ryuki Chapter 1, when he first meets her in the Naix Headquarters. During the conversation, Tokiko will ask you: "Are you a Frayer?" If you say no, then the story will progress as normal. If you keep saying yes, she'll ask you for the "Nil Number."
At this point, you won't know the nil number unless you look it up in a guide. You get the Nil Number from the Naix Headquarters at the end of the final and "true" ending. Here's the spoiler-laden context behind these answers, including where you get the Nil Number and how to unlock the secret ending.
How to find the nil number
During the epilogue, Mama tells Mizuki and Bibi to go to the Naix Headquarters. Tokiko's hologram should be waiting with a new script and the Nil Number at the Naix Headquarters. However, Mizuki and Bibi don't know what to do with it when they hear it. You might not even know what to do with it when you first get it.
There's no one Nil Number. It differs per playthrough, so you need to finish the game on your own.
How to unlock the secret ending
Return to Ryuki Chapter 2, where he first meets Tokiko at the Naix Headquarters. Again, Tokiko will ask: Are you a Frayer? Answer yes and enter the Nil Number in the prompt.
You and Tokiko will transport to an alternate dimension with nothing in it. She thanks you for helping her reach Moksha and offers you the option to tell Ryuki everything you learned from playing through the game's files. This means telling him everything from the name of the culprit, who's in danger, and all the little secrets you've squeezed out from each ending.
Nothing happens if you don't tell Ryuki. If you do tell him, then it will unlock the secret ending and skip to a future where you see the result of your choice. It's a very short route, but one that offers some interesting food for thought. After all, all these routes exist in tandem with one another in the canon.
AI: The Somnium Files - nirvanA Initiative is available for PC, PlayStation 4, Xbox One, and Nintendo Switch.
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