A/N: Finally, another 5D's MC, this one with a more regular update schedule planned, since it's a longer one. I'm hoping to update this bimonthly, alternating with a ZEXAL fic (otherwise I'd never touch some of my other fandoms :( ). If I don't stick to that, feel free to poke me until I do. I tend to respond to pokes.

The Arc 0 is the prologue arc; as a result, the arc and its chapters will be shorter than the others. The reason is that the two parts of the prologue don't go too well together in the same chapter, and the epilogue I currently have planned has the same problem. Splitting it like this seems to work better.

And that's about it from me. Enjoy, and let me know what you think.

Rerun
Arc 0: The Future Upon Them

An old pond;
a frog leaps in
the water sound

: An Old Pond :

Chapter 1

By the time he had realised, the future was already upon them. Uncontrolled energy had surged through and decimated half the city in its blast. The cries of a thousand innocent souls suddenly ceasing resonated like an explosion within his ears. They drowned out the wailing of his little boy: the child that had been born just hours before, and he'd held just that once.

There wasn't time to think that he might never hold that little baby again. He closed his eyes a moment – the silence roared in his ears – and opened them again. The baby was gone – to safety, he hoped, or else he had become another of countless victims sucked up in the blast.

And the cause of it: his research, his lab, the generator – they were all gone. There was nothing but a vast expanse of black that had swallowed him whole, and for a moment he simply hung, suspended, in the air, in shock.

Am…am I dead? he wondered. It wasn't an illogical assumption either; it was more feasible that he had crossed into the realm of death than his lab and its surrounding had been levelled to leave not even a trace of dust behind without touching him at all.

'Close enough,' a voice responded, much to his surprise. He could see no-one, hear nothing except his own breaths, now raspy as he strained his ears against the darkness, even as he struggled against whatever strange equivalent of gravity kept him in the air. 'You won't see me, Doctor Fudo.'

Many questions arose to his lips from that, but he kept them in check. A curious man he was, but not a foolish one. He sorted through his questions, asking first the most important one. 'Who are you?'

'I have been called many things,' the voice replied. Doctor Fudo noted its male tenor, as well as the metallic tint he had…almost as though he was automated: a machine, instead of a man.

'Indeed.' There was now a hint of amusement in the tone. 'You do your name credit, Doctor Fudo.'

The Doctor frowned at that. 'How is it you're able to read my thoughts?'

'It is not beyond my limits,' was the cryptic response. 'A great many things exist beyond the wall that appears before us.'

That raised more questions than answers, but the Doctor let it pass. 'What happened to the reactor?' was his next question.

There was a contemplative pause. 'What will happen is the question you should ask, Doctor Fudo.'

'Will happen?' The Doctor looked sightlessly about, despite the futility.

'In the future.' Another pause, but this time it wasn't contemplation, but…something else. 'I will show you.'

The darkness around him changed: shimmered, then lifted entirely to show two islands connected only by sea. They were like mirror images, reflections of one another: one crumbling with despair, the other bubbling with hope.

'Satellite and Neo Domino City,' the disembodied voice explained, and though the Doctor looked for speaker in the new light, he saw no other soul. 'This is the split that result from the Reverse Momentum. The split that threw half the city into the slums where they learnt despair, and the other half into the indulgence of the prospering new life they'd built, and greed.'

The Doctor frowned; he could hear bitterness in that voice, and mistrusted it.

'Oh, there was hope.' There was a hint of dark amusement with the bitterness. 'Hope in the form of a young boy from Satellite: Yusei Fudo.'

Doctor Fudo felt his breath catch in his throat at the mention of his son. 'He…he survives?' The relief is immediate: a cold wave that washes over him.

'For a time,' was the correction, which immediately caused the father's heart to plummet like stone.

'For a time?' The Doctor's throat went dry. 'How – why - ?'

'A chain reaction,' was the reply, and the scene began to move. A darkness rose out of the dilapidated island: the Satellite. It throttled the townspeople, those folk with their faces filled with despair. It throttled a dragon that briefly rose – a dragon he recognised: a key to the reactor. But it fell into the darkness too, as well as the duellist who owned it.

He saw the face, briefly. It looked just like his own. Yusei…

'And that is but one of many possible futures.' The voice, surprisingly, did sound sorry. 'And the kindest, perhaps.'

The scenes morphed: rewound themselves, and replayed to give different futures. Surviving the darkness that spread over Satellite, only to be killed by a friend. Surviving that, only to die at the hands of the one he, the father, had trusted hope and the future to.

'And even if that darkness is defeated…'

The scene changed entirely. Satellite and Neo Domino City were linked by bridges and prosperity had spread to both halves. But there was greed as well: higher violence rates, higher crime. And the terror that slowly descends, until Stardust Dragon and Yusei Fudo fall to it or fly into its heart to destroy it. Either way, no future beyond that shows his son.

And yet, Doctor Fudo finds himself unable to look away. The future had mellowed out a little: the image of false peace. Synchros flourished. The people revered the name of Yusei Fudo.

'A false peace indeed.' The voice sounded defeated now. 'Of course, it didn't last. Zero Reverse happened again.'

Zero Reverse? the Doctor wondered. But he thought he knew what it meant.

'The name they gave to the Reverse Momentum.'

And this time he saw it: the blast of negative energy wiping a city off the map. He saw the people suddenly consumed and destroyed before a scream to tear from their lips: could hear the agony of thousands of souls as they suddenly ceased to exist, and the terror as the effects, this time, rippled outwards, to other reactors, other countries, until the entire world was in a similar state.

And he was staring at a ruined world in which only four people walked: the last of a desolate mankind.

Then it was darkness again, the darkness that resonated with the future's horror and despair.

Doctor Fudo was silent, thinking of what he had seen until spoken to again. 'This future can still be changed – if the root of the problem is gone.'

'The Momentum,' Doctor Fudo breathed, before the heaviness in the air stifled him again. 'It's too late; the Momentum has already – '

'The past can be changed,' the voice, still unnamed, replied. 'It must be changed, before the Momentum can set the stage for these futures.'

The darkness began to lift again, but this time it gave way to nothing but dizziness. Light appeared, but it was dark, indistinct. The voice he'd been conversing it began to fade as well.

'You will have to change it, by making sure the Momentum is permanently destroyed...'

And then Doctor Fudo found himself swallowed by a hazy white, with screams resonating in his ears anew as the past rewound into the present.