The Fosiverse/The Multiverse Chronicles/Arc II

<tabber>Intro=|Incomplete Table of Contents|
Arc 1-The Beginning of Everything
Arc 2-As Darkness Approaches <- You are here!
Arc 3-The Battle of the Light
Arc 4-Interdimensional Travelers
Arc 5-Artificially Made Universes 
Arc 6-The Singularity Approaches 
Arc 7-The Future(???) 
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(If you clicked here, I'm sure you've already read Arc I. If you haven't, do it.)
|Chapter 0-Intro|
So far, the world had only light. With the Cascade going on, the number of worlds grew nearly exponentially. They were also connected at this time. So.. Why isn't the multiverse still so perfect? And why, exactly, can't we see Light in its purest form?
The answers to these questions will be answered here!
..I'm sure you've figured out how to use the tabber. If you haven't, though, remember, click on the button of the chapter you want to read. It should be the chapter after the one you're currently on! In this case, you click on Chapter 1!
|-|Chapter 1=|Chapter 1-The Buildup to The Fall|
Part 1-What is Darkness?
In order for us to find out what caused darkness to appear.. We first need to go over what darkness even is. There's actually some disagreement over what darkness is, and we can't ever learn about its properties if we don't know what it even is.
In a way, Darkness is simply the absence of Light. But it's more than that-Otherwise, there would have always been darkness, in the great voids where Light had not reached yet.
More accurately, Darkness is whatever is not of the Light. Evil is simply an absence of good.
This is a concept that's quite hard to understand at first for some of you, as you've been taught that good and evil are two competing forces... And in a way, that is true...
Likewise, Light is more than just an tool of creation. After all, even darkness has created things before. Light is also perfect in every way...
So, if someone were to use Light in the wrong way... Severe his connection to the Light.. Or gather desires contrary to the path of the Light.. Darkness would form in their heart.
But when Light is all there is... Where did the first sparks of evil come from?
Was there an evil spirit that brought evil into the multiverse? While that may be true, that can't be a full explanation, for we are simply pushing the problem back a layer-What caused the spirit to turn evil? If they were created evil, their creator was already evil, so the spirit did not cause evil. And if the spirit chose to be evil, then why?
We're back where we started. What caused the first sparks of evil?
This is a question that has been asked for millenia… So it's about time we finally reveal the answer to you guys.
Part 2-How Did the Cascade Work?
So, have you thought about your answers?
There are several myths about what caused the initial evil. Some say that it came from someone looking for something that they shouldn't have looked for-But this makes no sense. If there was some "forbidden world" or the likes.. There would need to be a reason why it was forbidden. And that would only make sense if there was darkness in that world. The "forbidden X" narrative might explain where darkness came in a particular world, but it can't explain the origin of darkness as a whole.
A far more accurate story is the story of it coming from greed.. And pride.
Recall what was still going on-The Cascade. In it, both Light, the seven beings directly from the original Source, and the beings that these seven people created, were all going on, helping to create new worlds, and further spread the light.
But eventually, two people would meet on this journey. Typically, when this happened, the people would settle on a compromise.. Or they'd work together to combine their ideas to form a world far better than just one could do alone.
You see, worlds were made of Light... But what made the properties different was strictly information. Information is the fundamental property of the multiverse. Not space... Not time.. But information. The rest are emergent. This will become important again later, when we deal with the Holographic Universe.
And sure, people were made purely of Light... But that doesn't make them all geniuses.
Different kinds of beings were created, as the intent of the seven direct creations of The Source was to make a variety of worlds, so that they may all exist in harmony. Harmony itself is a very powerful thing.. When many different kinds of things combine together.. They become far better than any one world does on its own. And the most efficient way of achieving this is by creating different kinds of living beings, so that they will come up with differing ideas, to make different kinds of beautiful worlds.
...And now, we finally have all the information we need to find the cause for The Fall.
|-|Chapter 2=|Chapter 2-The Fall|
Part 1-What Caused The Fall?
There were many different kinds of living beings.. Each with their own methods of spreading the Light, and all making different kinds of worlds.
But what happens when two fundamentally contradictory kinds meet in the same place, and attempt to form a world at the same time? For instance... One with gravity... And one without?
Normally, such a conflict would be resolved by simply determining who's domain the coming world was actually closer to... And letting the other side simply make their world elsewhere. 
But even though they all knew that there is an infinite amount of space, and thus infinite worlds could be made... Some may desire to have more influence than they do. Or they'd fight over one specific world.
Either way... They fought over the Light. (The light is the force of creation.. Well, it's more than that, but still-Worlds come from Light.)
Recall that darkness is simply the absence of Light. If something is contrary to the way of Light.. Then it is darkness.
Fighting over the growing Light, rather than simply splitting it.. So that everyone will soon have infinite of it... Whether it's their worlds being closer to the Center (which is meaningless-Have enough light outside, and they form their own sources of Light), or them just having more Light for themselves (Light is ever-growing. You just need patience.).. That would form darkness.
So, in essence, The Fall was the result of fighting over the Light. As they wanted to spread their own Light, and gather more for themselves than the amount that would create balance and harmony.. They have severed their connection with the Light, as they have acted contrary to the will of Light.
No longer having pure Light, Darkness appeared within the cracks. Or to be more accurate.. Darkness was the cracks.
Light brings freedom to all those who follow its will.. And Darkness is the opposite of Light. Meaning darkness would wish to imprison those who do not follow it.
It'd want to bring more people into the Darkness, to make it stronger.
This... is the origin of the Great Evil-The evil told in many kinds of mythology.
Part 2-The Spread of Darkness
Light and Darkness, however, have many things in common as well.
Just as Light can spread, so can darkness. While at first only existing within the hearts of the corrupted, it eventually influenced actions, and spread itself across the world. So, what happened next? Well, we know what happened next.
Remember this law? "The entropy of an isolated system does not decrease"
Yes, that was a thing well before your world existed. There were ways to break this law, but entropy never decreases on its own.
So the darkness would continue to spread throughout the light, until an equilibrium was reached-Where the entire world had the same density of light/darkness.
The influence of the darkness, alongside this second law of thermodynamics, meant that eventually, nearly everyone's hearts became half-light, half-darkness. There were only a very small number of people who did not gain darkness at all-The original seven creations of the Source, the Source itself.. And that's literally it.
Darkness also made its home on the other side of the world. The world was split into three realms-The realm of Light, the realm of Twilight, and the realm of Darkness. 
The realm of Twilight was the largest realm by far, and there was no real border between the two, at the time. The closer you got to the Source, the more pure Light there was, and the closer you got to the Great Evil itself, the more pure Darkness there was. It was a gradual shift. And as time went on, the realms interacted with each other, making less and less of it pure light, or pure darkness.
Part 3-The Formation of Heartless
There were other effects of the Fall as well. Now that darkness existed in the hearts of people, and Darkness is mutually exclusive from Light, if one had too much darkness, they would lack enough Light to remain as they are.
It was possible to be completely consumed by the darkness, if given too much.
Without any Light to continue the act of living, many simply died as a result. But other times, the darkness within them continued on, living as Heartless.
There are actually two kinds of Heartless, but for now, and for a very long time, only one existed-The Pureblood Heartless. We'll learn about Emblem Heartless far later on-So for now, cast aside everything you know about Emblem Heartless, and focus solely on Purebloods. We'll come back eventually.
When the heart is consumed by darkness, it vanishes. Sometimes, the body and soul itself remain as a Nobody. This process was already described in Arc I, however. But here is where it actually begins.
And recall how Darkness actually operates. It wants to corrupt others to fall into the darkness as well.
As a result, Heartless will attempt to take the hearts of others, and consume them.. Thus turning the victim into a Heartless as well!
...This would ultimately become a threat to the world.. But right now, there were so few that this wasn't a known threat.
Part 4-The Departure from Light
Why is it impossible to see the world of Kingdom Hearts now? Why did my Shadow Clone die when it entered said world?
Recall that when darkness entered our ancestors' hearts, it mixed in with the light. We thereby lack true light, only having it mixed within some Darkness.
Also recall that Light casts away the darkness, simply because darkness is the absence of Light.
If Pure Light hit us.. it would destroy the darkness.. Which partially now makes us up.
So just as being consumed by the darkness would kill us, and release a Heartless.. So too would Light kill us-Though there doesn't seem to be evidence of a "Darkless" resulting from it. However, that doesn't mean that the theoretical "Darkless" doesn't exist-They could in fact exist, and be the origin of the belief in "guardian angels"-At least the version that posits that said angels were in fact people that existed before. It's far easier to be consumed by darkness than to see pure Light, simply because of how little of it remains.
But that's not the only reason. Another reason is because the world of Kingdom Hearts is one of the very few that is still energy-based, rather than matter-based.
...That's right.. Eventually, many of us evolved away from being energy-based, and over to matter-based. But why? Well, in a way, it might be closer to devolution than evolution.
And Chapter 3 is where I go into detail as to how all of this happened.
|-|Chapter 3=|Chapter 3:Matter From Energy|
Part 1-The Origin of Matter
As any physicist would know, it is possible to transform matter into energy, and energy into matter. This is because matter is, in essence, simply a form of energy-This is why we measure an electron's mass in megajoules, rather than, say, attograms.
What you might now know is that particles exist as waves on a quantum field.
...Okay, most of you don't understand quantum field theory, so I'll try to keep things simple.
The world that you see, where matter interacts with other matter.. Can better be described as a set of many fields, interacting with each other.
When a part of a field is excited with energy, a particle forms in that field. Which particle depends on which field currently has energy.
...Okay, you probably don't know what any of that means. https://www.youtube.com/watch?v=ATcrrzJFtBY
Really, though, all you need to know right now is that particles come from energy. Specifically, oscillations inside of the field.
We also need to take into consideration what happened because of the Fall. Recall the properties of energy. It often gets transformed from one form into another. And with Darkness constantly colliding with Light, it'll often destabilize us. Matter happens to be the most stable form of energy there is (which you'll learn more about why later on), so with the threat of Darkness upon us, those made of matter would survive longer. Only the celestials that lived in the now quite small realm of Light could continue to survive in the pure energy form.
So, then, why does matter act differently than energy? And how does being matter-based prevent us from seeing something truly energy-based?
Each field works differently from the others, though what happens in one field can change the information within another.
And since we already know matter comes from energy, the question to ask might not be "Why does matter work differently than energy", but rather, "why can't matter-based life interact just fine with energy in its purest form?"
...When you look at it like that, the answer makes a lot more sense. When we evolved our mediums to specifically be within matter, what had become the most stable form of energy, while we gained the ability to not constantly be annihilated by Darkness.. We lost our connection to many of the other kinds of energy.
This is quite evident in the universe you live in, as it is why we can't see dark matter. We're only able to observe through the EM field, because we can only connect with matter-like energy, and dark matter does not interact with the EM field. Therefore, we cannot observe it in any way-Merely its effects on gravity.
This could also be the origin of the myths that state that before the Fall, we were quite "divine", but lost our divinity when the Fall occurred. In a sense, that is exactly what happened...
Part 2-The First Law of Thermodynamics
Within an isolated system, energy cannot be created or destroyed-Only change form.-Conservation of Energy
You are aware of this law, are you not?
In the absence of a source of energy.. Which ultimately comes from the Source itself.. This law applies. 
Energy is created as pure energy-Like that of photons.
Matter, in of itself, doesn't spontaneously get created or destroyed. The only way to get new matter is by converting enough energy into matter.
Depending on what world you're from, that might also create the side effect of "antimatter" being created alongside matter, but this wasn't originally the case.
And while matter is stable when it comes to interactions with energy.. It does decay over time into its fundamental particles.
And as it has lost its pure form as energy, and now exists as many particles at once, warping space-time itself (you guys do know about general relativity, right?), it must gather energy from elsewhere.
As a pure form of light, you were the energy you needed. And as motion only transforms energy, rather than depletes it, you could never run out.
However, when energy has to be manually converted through a matter-based system.. Energy is lost to the rest of the world as heat.
So, there's the first drawback of the conversion-Now you had to gather up your own kind of energy.
This might not seem that bad. The Source itself is a kind of energy, and if you could photosynthesize the energy.. You're all good, right?
...Matter doesn't work like the rest of energy. You can't spontaneously gain abilities..
In fact, pure matter can't even use magic on its own! (If you're wondering why creatures of matter are using magic, there is a reason. The key words are "pure" and "on its own".)
..What? You don't know what magic is?
...Looks like I'll need to give you an explanation of magic as well...
|-|Chapter 4=|Chapter 4:Magical Fundamentals|
Part 1-Okay, What is Magic Anyway?
...Actually, before I tell you how magic works, I have to first tell you about the layers of reality.
Part 1 (okay, for real this time):The Three Layers of Reality
Most of you viewers imagine that reality only has one layer, and has four funadmental things:Energy, Matter, Space, and Time.
...Nothing could be further from the truth.
There are in fact three layers to reality, and none of those four things are fundamental. In fact, matter is a kind of energy, and space and time are not all that different from each other.
The surface layer of reality is the one we observe. The physical reality. Where all we can see is matter, and the kinds of energy that interact with matter.
This is the layer where momentum exists as a separate form of energy, and where all particles of matter fall within.
Going down a layer, we find out that matter is simply a kind of energy. We find that time and space are interconnected, and form a 4-dimensional spacetime. Causality itself happens at the same speed as light (and darkness!).
Particles, and in fact all forms of energy, don't have fully defined speed and position-There's a fundamental uncertainty. So only a limited amount of information about a particle can exist at a time. Measure a particle's speed, and its position is now more uncertain-And the same is true the other way around. And there are many other pairs that work this way..
Likewise, before a particle is observed at all, it is in superposition.. We know this because different parts of the superposition have interacted with each other.
Superpositions act as a wave.. But they can collapse into a particle. This is most notable with light itself. We believe that as pure being of light, we were intertwined to this layer of reality, the quantum realm. We also believe the world of Kingdom Hearts is still within the quantum realm, which is another reason why we cannot simply enter it.
And if two bits of information are entangled, measuring one of them will collapse the other's superposition as well.
The speed of this effect? Instantaneous. Which is an exception to the "cosmic speed limit" that we had established.
This tells us something. And it lets us take a peek at the layer at the very bottom...
Space and time don't seem to be the fundamental nature of reality. Information is. Everything else derives from it. And seemingly, the laws of physics themselves, considering that they're not as absolute as they appear to be.
Part 2-Okay, Seriously, What is Magic?
Magic is what happens when you tinker with that very bottom layer. Since everything is made of information.. If you tamper with the information beneath us all, that makes everything up.. You're tampering with reality itself.
Summoning fire? That's as simple as adding the information that represents fire in the place corresponding to where you want to summon it.
The layer of information used to simply be one layer below us, and considering how we simply WERE energy, it was a lot easier for us to know about than it is now.
And it was far easier to interact with this information. Especially since that's how we created new worlds to expand the Light.
But after we devolved into matter-based life, we lost that connection. We lost the ability to do magic on our own.
Many worlds lack magic altogether for this reason.
|-|Chapter 5=|Chapter 5:The Aftermath
Part 1-The Process of Evolution
So, if matter-based beings cannot gain abilities on their own, than how could they have survived?
Well, since energy was being converted into matter, their forms remained somewhat similar. And as they already had a way to interact with energy, they just needed a way of getting it.
There were already fields of many plants in the many worlds.. Filled with energy. So it was as simple as.. eating the plants.
...Yes, our civilization got those traits first. Because we didn't start from scratch like your world did. In fact, we essentially now had ALL of the needs of a physical form of life. All drawbacks of either being made only of matter, or not being able to use magic, which is a result of being made only of matter. And we had essentially no way of using magic anymore, meaning we could no longer expand the Light and create new worlds. The Cascade, as a result, began to slow down..
But it wasn't entirely over. Sure, we couldn't create any new worlds, but the Light of the Source was still doing work on its own. However, the speed went back to how it was BEFORE life arose.
Oh, and remember those Heartless? They began to multiply.
Part 2-The Invasion
As was described before, Heartless are composed of darkness, and thus follows the will of darkness, the opposite that of light.
Hence, they would turn more people to the dark, to multiply.
But what is their end goal? To corrupt the many sources within the worlds, and eventually.. The First Source itself.
So, people of the Light searched for ways to combat the Heartless. They used the power of the Heart to form what is known as the Keyblade. This started a war between Light and Darkness... but eventually, it started to seem like the war would last forever.
Someone whom we now consider the Master of Masters realized the fruitlessness of the current battle, and decided he needed some way of ending the conflict. If he can’t find a way of defeating the Darkness, he can do the next best thing-Isolate the darkness from the rest of the world, so that they may do no damage. He looked into the future, and saw that eventually, things would go wrong, and the light would expire.
And so, he gathered six people, and told them it was to help gather Light, and bring order back to the world. But in fact, he knew this wouldn’t happen, and would slowly reveal this over time.
So, about the Keyblade. If one was attuned to it and their heart, they could use it to recreate much of the magical potential they once had-Because it acted as a sort of "proxy" to the magical part of the world. (You'll notice that many magic wands actually use the same concept!)
This would be how they fought back against the Heartless. But this would only delay the inevitable, as seven people’s effect on the total population of Darkness would necessarily be less than the rate of growth of Darkness. Even the later creation of the Unions wouldn’t be enough, it would simply delay the inevitable even further.
The Darkness would succeed. The only thing that could be altered is the aftermath of that success.
And so, the Master got to work.
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And that's the end of Arc II!
In Arc III, we'll be talking more about this conflict between light and dark, and the aftermath of it.
Then, you'll finally get to know exactly why we can't just travel from one world to another without very special techniques...
You'll learn precisely what fractured the cosmos.
Yes, fractured. Remember how I said at first, all the worlds were connected? How did you think they would have gotten separated?
The cosmos, what we know call the multiverse, was fractured. Each one of the pieces that remained became their own world.
Want to know how? Well, Arc III is coming soon! Until then, ask your questions, and check the Q&A section.
|-|Q&A=And here's the Q&A for this arc! Just like the previous, this is where your questions can be answered!
Q:I'm quite curious about what you're going to cover next. (Particularly "Arc 4-Interdimensional Travelers..."-Butterflyunicorn
A:Oh, the fourth arc? Yes, I can see why you'd be interested. It'll explain where we, the World Travelers, came from in the first place, and how we travel across worlds in the current time.
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