The following used to be on the Lemnisca Translations website, back before they started officially translating visual novels.

This page contains a translation of the “explanation” section of the I/O Setting Explanation Fanbook, meant to help better clarify some of the game’s concepts.

WARNING: This page contains major end-game spoilers. If you have not finished Route E’, please turn back now.

The Multilayer World Structure and Mutsuki’s Rescue

Forget the relationship between cause and effect for the time being Normally, it’s very natural for us to think that because there’s a cause in phyiscs, a result will occur. But like how there’s no answer for the question, “What came first, the chicken or the egg?” (the answer changes depending on how you look at things), there are some events that seem to have no cause or result. A lot of the events that occur in the story are the cause of many things, and at the same time, the result of them. Karmic retribution- what comes around goes around. It doesn’t mean that the strange events/phenomena that occur in the story were born due to the intentions and plan of someone who exists in the story (if you were to say that there is something that created it, it would be the “observation results” of the player who exists outside the story). Understanding the events that occurs in the game requires grasping everything as a flow of events.

The superposing was born from confusing two lunar eclipses.

That said, as a matter of convenience to advancing the story, let’s temporarily decide on a point for when the phenomena began. That point is the moment when the protagonists logged into Mutsuki’s dream. The four protagonists logged into the “lower stratum world” (the virtual world in the dream) from the beginning (The 1st Eclipse. Route A and B) and the end (The 3rd Eclipse. Route C and D) and possess their lower strata selves as “upper strata consciousnesses”. To the upper strata consciousness, the lower strata world is a world that’s the spitting image of the world they came from and a world where phenomena is set by “observation”. The upper strata consciousnesses that logged into the dream mixed up the 1st and 3rd Eclipses and “observed”. This became the reason why the consciousnesses transferred to the past from the 3rd Eclipse. In other words, because they made a misunderstanding that they were actually seeing the 1st Eclipse, it seems that their consciousnesses advanced in the direction of the 2nd Eclipse.

Furthermore, because the Hinata of the 3rd Eclipse had overlapped with {HE} and because the Mayumi of the 3rd Eclipse had overlapped with Ishtar, the upper strata consciousnesses at the 3rd Eclipse mixed up the real world and cyberspace and “observed”. To Hinata and Mayumi, who had flesh and blood bodies, it was the real world that was real, while to {HE} and Ishtar, who had bodies made of data, it was cyberspace that was real. As a result, the protagonists, now existing in an overlapped state, could no longer tell the difference between the two worlds. And thus, the superposing of the real world and cyberspace occurred.

Now then, recall how the superposing of Mutsuki’s dream and cyberspace occurred during the 1st Eclipse. It seems that the 1st and 3rd Eclipses got mixed up, therefore, the effects of the 3rd Eclipse’s “world superposition” appeared in the 1st Eclipse as well.

What awaited them at X Point

And thus, the “body and consciousness” of the 1st Eclipse and the “consciousnesses” of the 3rd Eclipse aimed for the 2nd Eclipse- the X (Cross) Point in time where time intersected- together. Just like how this was probably like trial and error to the player as well, it was probably endless trial and error to the protagonists. They may have lost sight of themselves in certain attempts, and in other certain attempts, {HE} and Ishtar may not have met at the X Point. Even so, they continued to seek for the possibility where everything was superposed.

And at the end of countless attempts, they reached the Core, where Mutsuki was sleeping. But the passcode to awaken Mutsuki had been lost. Their only remaining method was to log into Mutsuki’s dream and ask her consciousness…

In other words, they returned to the point where their journey and the phenomena’s start had been set. You could say the phenomena in the story had no beginning anywhere, but on the other hand, even if it did have a beginning, that would be the correct spot. The relationship between cause and effect was finally becoming vague.

The endlessly repeating logins and logouts

And as the protagonists log into Mutsuki’s dream over and over and over again, they become aware of a certain problem. No matter how many times they log into the dream, as long as Mutsuki continues to sleep, then even the Mutsuki in the lower strata worlds is asleep, so the end up logging into the dream even while being in the dream. And this repeats endlessly.

Also, while they’re unable to solve the login problem, yet another problem comes to light. After they successfully get the passcode source from the Mutsuki in the dream, they log out of the dream and assume they awaken Mutsuki. So what happens when she “speaks of” the passcode to them as if she’s telling them for the first time? The possibility that that world is also a dream they’ve logged in to in order to ask for the passcode is born. And so they log out from the dream and… this process repeats ad infinitum. In the first place, the protagonists in the lower strata world being able to log into Mutsuki’s dream is thanks to the world’s laws of physics being warped by the existence of the upper strata consciousness. In other words, that means if the world they’re currently in isn’t in a dream, then they couldn’t log into the dream. Just what is going on? The story then proceeds to tell us this:

“This escapeless infinite corridor of dreams is like a chain of possibilities produced by {Marduk}. The initial cause was nothing more than an ordinary malfunction. But now, {she} is acting as a means to secure her own ego- that is, {Enigma}. Almost like a child clinging to her mother.”

Is the act of trying to wake Mutsuki up in this infinite corridor of dreams not something like executing a recursive call with an error in it? … The protagonists start to think this. Have all the programs (actions) up until now been full of bugs that caused an infinite loop? Was there a mistake with the end conditions? Have they lost sight of their position? Is performing a reset the only way to end the infinite loop? In the first place, do they exist…?

“How long has this been going on? What reason is there to be here? Just where did this consciousness come from?”

That’s right. The infinite corridor we see at the very start of the story may not have been the place it started, but rather the place they arrived at after endless repeats.

That which appears to be infinite is not infinite.

But please remember. Were the protagonists’ actions really an infinite loop? No, they weren’t. Even if it appears to have been a loop, they slightly changed the situation and arrived at the X Point. And the world they’re in is a world where phenomena is set via “observation”. The protagonists are not looping in this situation, but rather “observing” every possibility through trial and error. The instant they “observed” that, {Marduk}’s final resistance begins in an attempt to keep clinging to Mutsuki. While the protagonists battle {Marduk}, they question all their actions up until now once again.

-Does Mutsuki want to sleep? She wants to wake up. She sought help from within the dream.

-Since all the worlds and all the phenomena were in a dream, perhaps “they” don’t actually exist? Isn’t it possible they’ll also appear if they end the dream?

“I” am here. If I’m an illusion, then where is the “me” that’s thinking that? There’s no meaning to thinking about the possibility that I don’t exist.

If their thoughts waver here, then the trial and error isn’t over yet. But in the blink of an eye, the protagonists stop wavering. And thus they go out to greet the end of the dream world.

The world they needed to return to was all of them.

At the end of the battle, Ishtar types in all the passcodes and stops the {AIO} system. Mutsuki’s consciousness starts heading towards awakening. Now left completely alone, {Marduk} attempts to cling to the protagonists this time. On the verge of logging out, the protagonists are thrown one final question.

-Now that Mutsuki’s awake, where’s the world we need to return to? All of them. All of the actions they took up until this point, all the events and phenomena, and the existence of all people was necessary. So the world we need to return to is all the worlds.

“That was the moment the separated ‘myself’ and the ‘world’ (in this context “world” refers to the sum total of the images everyone other person except for myself has of me) superposed.

“And all my other selves are none other than me. The ‘me’s who exist in this multilayered world. Amongst them might be my past self who finds it difficult to accept my current self, and my future (possible) self who my current self finds difficult to accept. But the protagonists accept all of them.

“By understand that the world we needed to return to was all of them, I’ve found myself on both the inside and the outside.”

Let’s organize all the details up until this point. In Mutsuki (and by extension {Marduk})’s dream world, all those possibilities existed. That’s why it seemed like it was looping in circles. And all those loops- no, possibilities- were all correct, so not a single one of them was meaningless- they were all necessary.

If it hadn’t been for Mutsuki and {Marduk}, the protagonists and other characters may not have felt any sense of reality.

Let’s look at I/O’s story from other viewpoints.

Now then, do you understand the story’s major flow? From this point on, let’s try to view I/O’s world from different viewpoints in the story.

When the player (the consciousness that exists outside of I/O’s world) starts the game (begins observing the world), there are four stories (four worlds, or possibilities) available, from Route A to Route D. Because it’s a game world (virtual world/lower strata world) to the player, all sorts of strange phenomena occur. What’s more, it’s also possible to mislead the protagonists. So the player first tries misleading the protagonists in order to make the story coherent (by trying to make the four possibilities cross over with each other). When that happens, Route E appears, making it a story (world) where two loops exists- from the 1st Eclipse to the 2nd Eclipse and from the 3rd Eclipse to the 2nd Eclipse.

From there, more intervention occurs. Mutsuki is awakened. That becomes the cause of it becoming a story (world) that includes Routes C’ and D’.

If the people who exist in the world of I/O learned that the world had changed appearances, they would probably think it were unnatural. Maybe it can be thought that as a result (present) of Mutsuki waking, the cause (past) occurred. But the player easily makes the past clear to solve this issue and so no contradictions whatsoever can be felt.

When the player plays (observes) Routes C’ and D’, Routes A’ and B’ are unlocked this time. Even though these are futures born from the same past, because the result diffuses, this can be thought of as unusual from the world the player is in (though it may be difficult to notice as unnatural since it’s a natural thing in fiction). But if you look it at it from the perspectives of the people in the world of each separate ending, there’s no contradiction at all.

Apparently, if you look at something that seems to be a contradiction by changing your viewpoint with that of someone seeing that contradiction, it’s no longer a contradiction. Can you understand this interpretation? Even if you can’t, that doesn’t mean someone else can’t. Of course, this interpretation is not absolute either. Something that’s a contradiction to you may not be a contradiction to someone else-.

“The world you’re seeing may be different from the world others are seeing.”

“The world you’re aware of may be nothing more but the extension of someone else’s world. Your world might be creating someone else’s world.”

As long as “others” and “mutual understanding” evade you, you may lose sight of even “yourself” in the future. So recognize the importance of “mutual understanding once more”-. That is what the game tries to tell us.

The roles the protagonist played in the four routes.

Finally, let’s abridge the whole story’s flow and go over the actions of the protagonists of Routes A-D.

First of all, Hinata’s role was to reclaim the memories of his forgotten past. Without those memories, it would be very unlikely that the others would realize that they had obtained the passcode source in Mutsuki’s dream even if they did obtain it.

Ishtar α’s role was to pass the rosary down to Mayumi and to cause the meeting between Ishtar ω and {HE}.

Ishtar ω’s role was to use her pure feelings to protect {HE}.

Finally, {HE}’s role was to awaken Mutsuki (to produce a new world). A role befitting the one who is referred to in the same way as the One God.

Hinata had the motive, and {HE} acted in response to that. Ishtar α caused the meeting between Ishtar ω and {HE}, and Ishtar ω’s feelings protected {HE}. Motive, action, guiding force, and personal feelings. If even one of those had been lacking, then it would have been impossible to wake Mutsuki up.

And just like the time where the player advances through the game, there were probably many occasions where Mutsuki couldn’t be awakened because one of those were lacking. Even when playing from the player’s standpoint, each route can’t be cleared on the first try, and it is by advancing in the other routes that it is possible to complete the first route. In the first place, the point in time where the game begins is the start of the trial and error “to the player”. The protagonists may have been repeating the same trial and error way before that. This is where we must remember Hinata’s thoughts just before he woke up Mutsuki.

“In the end, exactly how many times did we repeat the same things? There’s not even any definite guarantee that this is actually reality. No, it doesn’t matter how many times we repeated them. It doesn’t matter if this is reality or not. I decided it, didn’t I? That we are… That our reality… Is certainly- right here.

And so I say the words that I’ve repeated possibly several times, hundreds of times… thousands of times, millions of times, or possibly billions of times once again.

‘Good morning, Mutsuki…’.”

The meaning of Route E’s final three choices.

1: Mutsuki “wants to wake up”

-> This sets the end condition of their actions (the future)

A reconfirmation of the goal of all their actions up until this point. Mutsuki certainly wants to be awakened.

2: We’re “here!”

-> This sets their current position (the present)

They’re in a superposed world where infinite possibilities are overlapping.

They’re not diving into their own minds.

So it’s not impossible to change that which has already occurred.

3: The world they need to return to “is all of them”.

->This sets their return address (the past)

All the events up until the point Mutsuki was awakened, even the actions that ended in failure, were necessary.

So the world they needed to return to (change?) was all of them.

The instant they choose only one world to return to would be denying all the actions they took up until that point.

What is the structure of the story and the histories that result from it?

First, let’s review the story’s basic flow. The game’s structure has Routes A-D gathering towards Route E. Route E mainly depicts the basic conflict being resolved at the 2nd Eclipse that occurs at the “X Point”. The past of the “X Point” is based off of Routes C’ and D’, and then in branches off into Routes A’, B’, and E’. And at its center (no, perhaps we should call it its “root”. Its position is not set, after all) is Route E. In other words, the future depicted in the world of I/O becomes the ending of Route A’, the ending of Route B’, the starting point of Routes C and D (which are basically the same future) before the transfers to the past begin, and Route E.

The “certain histories” shown in the History unlocked after clearing the game are the ending of Route B’, the ending of Route A’, the starting point of Routes C and D, and the other result where Nabu’s plan is activated (though that might be Route E’, which has surpassed time and space). In other words even if the ending of Route E (which occurs last chronologically) is not the history of Routes C and D, then where it continues to and where it continues from becomes unknown.

What are each of the discovered results and the newly born world?

It’s written in the History, but now let’s look at each of the results carefully. First, let’s check the history that resulted from Route B’. In this story, Enlil destroys the quantum computers with her own hands, and all the Shadow Nulls vanish. {Marduk} and {Ashur}’s consciousnesses also depart on a journey somewhere (Enlil worries if they’ve gone to “Heaven” or not), and {HE} and LEM (A) also depart. But unfortunately, Ereshkigal, who was in {Enigma}, is left behind. Hinata, who has separated from {HE}, begins to walk on his feet with Mayumi by his side… The consciousnesses in cyberspace vanish, and those in reality have been left behind, so this probably symbolizes a so-called “Gene” ending. Here, Sakuya has not been “observed”, so humans cannot see her as she is.

In the history that resulted from Route A’, Hinata is successful in rescuing Sakuya from eXarch with the help of the quantum computers. He is also helped in the shadows by the Shadow Null of Mitsuhiko, his deceased father. Nabu tries to stop this by attempting to destroy {Ashur}, but in the end, he can’t bring himself to destroy something he created. Nabu’s plan never comes to fruitation, and Hinata and Sakuya become a couple as they greet the start of the new era… But in the result where Sakuya is found, Mutsuki can’t be seen.

In the case of the starting point of Route C and D, the superposed lower strata world is completely destroyed at the same time Mutsuki dies. However, this future is the situation where Mutsuki is not awakened in Route E. It should be impossible for there to be a future that escapes from “I/O”‘s superposed world. But what if the Multilayer World Hypothesis that Wadatsumi Kaiji proposed is true…?

The ending of Route E seems to resemble the endings of Route A’ and Route B’, but has slight differences. Ereshikigal took Mutsuki’s place in the vacated {Enigma}, and the Shadows that started with LEM have apparently rebooted. What about Sakuya? And what about Mutsuki? Will yet another story start from that point onwards?

And last but not least is the ending we see in Route E’. Is it a world where Nabu’s plan is successful, where the boundaries between realspace and cyberspace, as well as flesh and data, has vanished? We don’t see any specific description. However, the adults watch as the boys and girls depart on a journey to discover everything. Those lights form two Penrose triangles, which then “superpose” and become a hexagram. And then the two opposites who possess the eyes that see through all (Ereshkigal and Enlil) overlap with it. That represents the birth of the universe and the origin of the four opposing singularities. Before long, a boy and two girls appear out of nowhere and fool around in the ocean (the primordial sea)… Soon after that, perhaps they returned to the place(s) they needed to be. Is that place Dilmun? But there are also those who walk with them. If that’s the case, then surely…

The observed futures and their flow

Route C’ Ending Route D’ Ending

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Route E’ Ending

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Route B’ Ending Route E Ending Route A’ Ending