Author's Note: "It" is the entity Optimus speaks to in the episode "The Return of Optmus Prime Pt. 2" that tells him about the Transformers first encounter with the Hate Plague. No joke, the script for the episode refers to the entity as "It."
"Is Mr. Prime okay?" Remina asked concernedly as she looked up at Optimus. He stood perfectly still with his optics glowing faintly.
"Optimus'll be fine" Ironhide reassured her. "An he'll find a way ta turn that interstellah glutton inta space dust!"
"Autobots alert" Omega announced. "Object approaching. Intent: unknown."
"Can you give us a visual?" Wheeljack asked.
A holographic screen appeared in front of them all. It showed a dark red orb with a large pale spot. Upon seeing it all of the humans turned pale, looks of fear on their faces.
"That's it. That's the thing that destroyed Earth" Iwai managed to say.
"Omega, how long until that thing reaches us?" Wheeljack asked.
"ETA four kliks" Omega replied, his tone emotionless as always. At the moment Wheeljack envied his inability to feel fear.
"Can we outrun it?" Bumblebee asked.
Omega ignited his rockets and sped away. As fast as he was it was clear right away that the monster planet was still gaining on them.
"Hurry Optimus" said Bumblebee anxiously.
Inside the Matrix-space a face appeared before Optimus. It resembled a fanged skull made out of a glowing yellow wire-frame. Despite It's macabre appearance Optimus sensed only benevolence.
"The creature you speak of is known to us, though not in its current form. Do you know how Cybertron came to be?" It asked.
"I know the story of Primus and Unicron" Optimus replied. "It's an ancient legend but its never been confirmed."
"No, it is fact" said It. "In our reality Primus, the Lord of Light and Order, sealed away both himself and Unicron, the Chaos-Bringer, into lifeless planets to prevent Unicron from destroying the Universe. In another reality however things did not go so well."
"In this other reality Primus was mortally wounded in battle. He was able to seal Unicron away but he then succumbed to his wounds. In that reality there never was a Cybertron or Transformers. Unicron's prison was lifeless but in time it was settled by a race of beings that terra-formed it into a paradise."
"Oh no" said Optimus. He realised where this was going.
"Exactly" said It gravely. "Unicron was able to take control of the world in which he was sealed, mutating its biosphere into monstrous horrors and poisoning its atmosphere. In time he was able to corrupt the planet itself into a world-devouring abomination and resume his campaign of destruction. It was interrupted however when he was drawn through a wormhole into this reality."
"Where he destroyed the Earth and its solar system" said Optimus grimly.
"Then I know what I must do" said Optimus firmly.
Once more light filled his optics. When it cleared he was back aboard Omega Supreme.
"What's wrong?" he asked as he noticed how afraid everyone looked. They all turned to him, their fear turning to relief.
"Optimus, the thing that ate the solar system is after us" Bumblebee exclaimed.
"Please tell us you found something useful" Wheeljack pleaded.
"I did" he replied. He glanced over at the holo-screen and saw just how close it was. There was no time to lose.
"No time to explain, everyone hold on." He hurried over to an equipment rack and picked up a rocket pack which he hastily put on. "Omega, activate a containment field and open the hatch. Close it again as soon as I'm out."
Omega did so. A transparent orange force field flickered into existence as the hatch opened. It would allow Autobots through while keeping atmosphere in.
"Optimus, what are you doing?" Bumblebee asked in dismay.
"Yer not goin' to face that thing by yerself are ya?" Ironhide added.
"Mr. Prime please don't! It's too dangerous!" Remina cried.
"Don't worry" Optimus replied. "Everything's going to be all right."
With that he jumped through the containment field into outer space. The hatch closed behind him.
"Everybody, look at the holo-screen!" Wheeljack exclaimed. He pointed at the screen and all eyes turned to it.
Optimus rocketed through space towards the monster planet. It was close enough now that he could make out the full horror of its appearance. The pale spot was in fact a gigantic eye. Smaller eyes dotted its dark red surface. Beneath the main eye was a giant, hideous mouth filled with sharp, pointed teeth.
Most would have frozen in terror at the sight of the creature. Optimus Prime however was made of sterner stuff. As he flew he opened his chest compartment and drew out the Matrix.
Unicron, you have caused untold suffering and death he thought. I was too late to save the Earth of this reality but by Primus I swear that I will stop you. No more lives will be lost to your evil.
He dove through the planet's atmosphere, his armour easily handling the intense heat generated by atmospheric entry. He could now make out the surface, a grotesque landscape of tubes that resembled organic intestines and writhing balls of tentacles. Most of his attention however was on the great cavernous maw and the rows of mountain-sized teeth that lined it.
Without hesitation Optimus flew right in. As he plunged deeper into the stygian darkness he pulled open the Matrix's outer casing, letting its brilliance shine forth.
Unicron's main eye widened and his mouth opened wide but in the vacuum of space no sound issued forth, only a stream of pure blue-white light. Tremors rocked the monster planet's dark surface as it shook. Glowing cracks raced across its crust. With a final convulsion Unicron blew apart in a wave of pure energy. Fragments crumbled into dust as they were sent hurtling away.
Unicron, AKA Planet Remina, was no more.
Aboard Omega Supreme everyone had to shield their eyes and optics from the light as they watched what was happening on Omega's holo-screen. The energy wave washed over them harmlessly. A few pieces of rapidly disintegrating debris slammed into Omega's hull but his armour wasn't even scratched and those aboard barely felt anything.
"Optimus… Is he…?" Bumblebee asked anxiously.
Ironhide pointed at the screen. "There!"
Everyone cheered as they saw Optimus come flying out of the remaining bits of debris, no worse for wear. He headed back towards them
"Omega, slow down and prepare to open the hatch" said Bumblebee, his voice filled with relief.
"Understood: engines decelerating" Omega replied.
Optimus was greeted by a mix of excited cheers and concerned questions about his well-being. He modestly accepted the congratulations and reassured them all that he was fine. Remina and the others were gladdened that the monster that had destroyed their world had finally been stopped.
"So… what now?" Daisuke asked once they had all calmed down.
"Now we'll be going back through the wormhole to our own reality" said Wheeljack.
"We'd be more than happy to bring you with us" said Optimus. "You can make a new life for yourselves on a new Earth."
Remina, Daisuke and the others all looked at each other, barely able to believe what they were hearing.
"What did I say about miracles?" Daisuke asked with a grin. He turned back to Optimus and said "we'd love to tag along."
"Thank you Mr. Prime. For everything" said Remina.
"We're always happy to help, Miss Oguro" he replied. "Omega Supreme, take us home."
After the Autobots and their new human friends returned to the Ark, Optimus contacted Astoria Carlton-Ritz, now the CEO of Hybrid Technologies, and explained the situation to her. Though somewhat baffled by the whole thing she readily agreed to provide room and board for the other reality's refugees.
Meanwhile Perceptor got to work crafting identities for them. Birth certificates, passports, everything they'd need to operate in their new home. Daisuke requested that he be given a new name, Oguro Daisuke. To Remina's joy, once everything was in place, Daisuke legally adopted her. Iwai and Yumeno got married (with Daisuke as best man and Remina as maid of honour) and adopted the boys.
Once they had gotten accustomed to their new world (not too difficult as it was basically the same aside from not being quite as technologically advanced), Daisuke got a job as an engineer in Hybrid Technologies Tokyo division. He was able to afford a modest but comfortable apartment, and to send Remina to a good school where she studied hard to become an astronomer like her father had been.
Against all odds they had not only survived losing their world but had also found a new home where they could live in happiness. Daisuke had been right, they had gotten another miracle after all.