"Holy sweet mother of god!" Luna said as she was eyeing down the doomsday weapon of a demon.
"Does she ever die?!" Rainbow Dash asked.
"NOTHING CAN STOP THE END OF THE WORLD LADIES!!!!!" Sunset Satan said in her new colossal form, to her. Equestria looked like a little blue marble, the other noticeable changes, was that she now had a massive rune behind her devil form, one that constantly gave her strength, and by looking at it made her even stronger, other than than she had dark red spiky tentacles spurting out from her new dragon-like body, which in turn was the size of Equestria itself, what's more is her wings and claws looked even sharper, and she was covered in archaic markings from head to talon, "ACCEPT YOUR FATE AND GIVE IN TO THE DARKNESS!!!!!!"
"There's no way we can damage her now, let alone even touch her!" Twilight said with fright.
"There is one way, it involves the humans as well though." Luna said as she turned to Twilight and friends, "Our world and their world are linked, if we could harmonize the flow and stabilize the paradoxical effects of two of the same, we might be able to unify with the humans and gain a power to match that of the demon's!"
"There's one little detail i have to warn you about though." Celestia said, "In this new form you gain, you will only have a limited time to defeat Sunset Satan, before you turn into ponies again."
"We're on a time limit eh?" Rainbow Dash said, "Sounds like my idea of a challenge!"
"Alright then, Celestia. We'll combine our strength and open up another portal to their world!" Twilight said, "If we can remove the double life form paradox effect, we'll have a chance of defeating Sunset Satan once and for all!"
As the three princesses put their horns together and initialized the flow of magic, an earthquake started to form as a rainbow coloured ring appeared in the ruined ceiling, As their concentration grew, the ring turned into a rainbow coloured vortex, one which eventually morphed into a clear view of Canterlot High, Where dozens of confused humans were gazing throught the new portal at their pony counterparts.
"Beings of Canterlot High." Celestia announced, "We're in dire need of your aid, Sunset Satan has returned, and we need your undying bonds to give us the strength to defeat her!"
"Twilight?" Said a human with a Chad Sexington look on his face.
"Yes, Flash, it's me, this is my true self." Twilight said to him, "It's time to save both of our worlds!"
"The worlds we live in will both be destroyed if you don't help us now! Please, we need your spirits, it's the only way to save the worlds from destruction once more!" Twilight said to them all, "If Equestria goes down, Canterlot High goes down as well!"
As she finished, the ceiling of the high school started to crumble into pieces and shatter the building's foundations, causing a cataclysmic earthquake to occur.
"We need you."
"Very well, Princess Twilight! We'll do what we can." Flash said as auras of magic formed around them all, "Our power is now yours!!!!"
The stundents were now making pushing gestures, as they performed this, a stream of their auras wrapped the ponies in a veil of magic, magic which morphed them all into humanoid ponies which i called during the movie, "FINAL PONY-HUMAN EVOLUTION TRANSFORMATION!!!!!" the only noticeable changes were that the humans were now in Equestria, watching from the sidelines on bleachers from afar, also, the Hu-Mane 6 were now coloured completely in rainbow energy, and Celestia and Luna had become giant balls of pure light, As they all took to the skies and passed the stratosphere, they encountered the god-sized demonic creature once more, the bleachers were also oxygenated and allowed the humans to follow the Hu-Mane 6 during combat.
"Alright everyone! It's time to save the worlds!!!!" Twilight announced.
"ETERNAL FRIENDSHIP, GIVE US POWER!!!!!" Everypony and body said in perfect unison, allowing Twilight and friends to gain limitless power and an intensified rainbow aura.
"YOU PONIES WISH TO CHALLENGE ME?! THE ALMIGHTY SUNSET SATAN ULTIMA CATACLYSM FORM?!?!" The evolved demon asked, "BIGGEST MISTAKES OF YOUR SOON TO BE FINISHED LIVES!!!!!!!"
As the eight godlike humares charged at the demon's final form, Sunset Satan generated a barrier around herself, bitchslapping the 8 friends into the deepest reaches of space.
"How is she doing this?" Celestia asked Twilight.
"She's harvested all the dark energy from Equestria and Canterlot High, thus making her immortal and all-powerful!" Twilight grimaced.
"If we don't strike her down now, it's the end of our worlds as we know it!"
"THAT'S YOUR PROBLEM THOUGH. I CAN'T BE STRUCK DOWN!!!!!" Sunset Satan boasted to the 8 rainbow coloured mares, "As long as i have the sigil, and am free from the chains of a human body. I AM GOD LIKE!!!!!!!!!!!!!!!!!!!"
"And just to prove it....." She paused before clicking her fingers, "NOW YOUR WORLD IS ABLAZE! AND THE END OF EQUESTRIA IS NIGH!!!!!!!!!!!!"
True to her word, Equestria was now on fire, the once luscious blue ball which Twilight and friends called home, was now a blazing fireball of death, with everypony on it burning alive before spontaneously combusting into thin air.
"THIS IS THE CATACLYSM OF YOUR WORLD!!!!!!!!"
"This is truly horrible!" Celestia said as she was watching the destruction of her world and kind, "If Equestria gets destroyed...."
"Don't think about it, Princess. We'll stop her before we lose our powers!" Twilight said to her with confidence.
"IN 5 MINUTES, EQUESTRIA WILL EXPLODE. AND WHEN IT DOES....." Sunset Satan stopped for a moment, "YOU'LL LOSE ALL YOUR POWERS!!!!!!!!!!!!!!"
"5 MINUTES?!?!" Rainbow Dash grimaced, "I was expecting it to be longer than that!"
"We'll do this in less than 5 minutes, Dash. Don't worry about it." Twilight said before charging into the forcefield, causing it to crack a little, but not break completely.
"OK girls, a few more of those and she'll be defenceless!" She said as she charged into the forcefield once more with the other ponies behind her.
After 5 or so charges, the forcefield finally shattered, leaving the demon completely and utterly defenceless.
"MY SHIELD!!! WHAT HAVE YOU EQUINES DONE?!?!" Sunset Satan said as she charged up some final level dark magic in hands, "I WILL NOT BE DESTROYED!!!!!"
The countdown clock now read 4 minutes, and Equestria was starting to break into cracks from afar.
This is gonna be messy, girls!" Twilight issued the warning as they were impaling Sunset Satan with their new forms' spear magics.
Sunset Satan tried to shake them off with dark magic, but Twilight and friends were masters in the arts of avoiding the darkness, and quickly evaded a dark aura sphere barrage from the demon.
"THIS WILL NOT END WITH MY DESTRUCTION!!!!" The demon denied Twilight's victory, "I WILL DESTROY YOU PATHETIC, CHILDISH, EQUINES!!!!!!!!!!!!!!!!!!!!!!!"
Whilst she screamed the last word, a dark magic aura was intensifying around her, knocking Twilight and friends into the sun and landing thousands of 3rd degree burns all over the girls, causing them to faint.
"Twilight!" A voice shouted as she was fading to black, "GET UP!!!!!!!!!!!!!!"
All she could see was nothingness, complete and utter darkness, lying on what looked like a black floor with eyes shut, a voice suddenly turned into a hand and reached out for her, causing her to wake up in the dark realm.
"Where am i?" She asked upon awakening in the new world.
"Twilight." The voiced hand once more said, "Get up. You must save the worlds."
"But how? We're all dead by means of burning to death, and what's more is that i can't see any of my friends here."
"You musn't lose hope, even in the darkest darkness. You can still win and save Equestria!"
"You're right, as long as i don't give up hope, nothing can stop us!" Twilight said as the dark realm turned into a white realm of light within the blink of an eye, what's more is, once the darkness fully dissipated, Twilight's friends and rulers materialized in the room all around her, "We're the only ones who can win! Now let's awaken our true powers!"
As the light realm returned into Equestria's galaxy, Sunset Satan was shocked to see Twilight's new final form.
Twilight was now coloured completely in light, and all 7 of her friends were creating another sigil behind her, which like Sunset's, gave Twilight limitless strength and power, and morphed her hair into a curly hairstyle of pure beauty and covered in rainbow energy, what's more is that she was now covered in white armour covered with rainbow coloured veins, and carrying two swords in waistline scabbards.
"SO." Sunset Satan said at the new ultimate form Twilight Sparkle, "YOU'VE ENGAGED YOUR ULTIMA FINAL FORM EH? THIS WILL BE A GOOD FINAL MATCH, NO HOLDING BACK THIS TIME!!!!!!"
"Let's dance, you cold hearted devilspawn of a villain!" She said whilst charging at Sunset Satan as the countdown clock struck 3 minutes, and Equestria started conjuring pillars of fire from the burning grounds.
Whilst in outer space, Sunset Satan and Twilight Ultima were now slamming the other with godlike sword-magic whilst firing godlike spells from their palms/claws.
"YOU CAN'T WIN, TWILIGHT!!!"
"SAYS YOU!!!"
Twilight then flew underneath Sunset's dragon part to try and deal some damage down below, whilst avoiding the dragon's red spiked tentacles and dodging a torrent of fire. As she flew underneath, she started stabbing and cutting the demonic dragon's underbelly and stomach, in turn causing Sunset Satan's demon half to clench her black heart and flinch a little as she screamed in agony.
"OK I'LL GIVE YOU POINTS FOR THAT MANEUVER." She said in pain, "IT'S NOT EVERYONE WHO'S BEEN ABLE TO DEAL ME PHYSICAL PAIN. ACTUALLY SCRATCH THAT, IT'S BEEN NOBODY!!!!!"
"You seem to be struggling a little, Sunset Satan. Are you sure you don't need to head back to Sunset Shimmer's body to replenish your health?" Twilight taunted the demon.
"DON'T YOU EVEN DARE! TWILIGHT. I SPENT 36 MOONS TRYING TO ESCAPE THAT PRISON AFTER SUNSET LEFT CELESTIA'S CLASS, AND WHEN I FINALLY ESCAPED ON THAT NIGHT, I KNEW I WAS GOING TO HAVE MORE THAN ONE FINAL DUEL. THAT'S WHY YOUR ELEMENT OF HARMONY ONLY SEALED ME AWAY, INSTEAD OF DESTROYED COMPLETELY!" Sunset Satan explained in fury.
"We sealed you away?!" Twilight asked.
"YOU'VE ONLY SEALED AWAY DARKNESS WITH THOSE ELEMENTS, WHEN YOU SHOULD HAVE BEEN KILLING THEM IN YOUR NEW FINAL FORM!!!!! BUT THEN AGAIN, WE ALL MAKE GRAVE MISTAKES!!!!!"
"Sealed or not, we're still going to stop you once and for all!" Twilight said as her sigil warped in front of her and started conjuring up an enormous purple laser.
"SO WERE ENDING THIS WITH A LASER-OFF EH?" Sunset Satan said as her sigil did the exact same thing and made a red laser.
"No holding back?"
"NO HOLDING BACK!!!!"
After the sigils started to glow their respective colours and get bigger and bigger, they eventually turned into purple/red circles of pure energy.
"FIRE!!!!!!!!!!!!!!!!!!" Said both battling entities, The lasers crashed into each other at the same time as they were fired, and Sunset and Twilight were focusing all their energy on the opponent's laser, as this went on for a minute, Twilight started to flinch, and Sunset's laser came closer and closer to Twilight's position.
"Don't worry, Twi." Said Flash, "We've got your back!"
The humans started focusing more energy into Twilight's laser, it took time for all of the humans' auras to maximize the power of Twilight's laser, but it was worth it as Twilight's laser was now 3 times the size of Sunset Satan's laser, which in turn pushed the laser straight back into Sunset's direction and completely shattered her red death laser and vaporized the demon once more.
"THIS-THIS IS THE POWER OF EQUESTRIANS AND HUMANS IN HARMONY?!" She said as she was peeling away in the rainbow laser, "NNNNNNNNOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
As she screamed her last word, Sunset Satan exploded in a veil of demon fire and rainbow fire, as the explosion faded away, the countdown clock vanished, and just in the nick of time with 10 seconds remaining, and after the clock vanished, Equestria returned to it's usual beautiful status, and the healing light, magically returned the humans and ponies to Canterlot Castle.
After they landed in the castle, all the natural disaster damage caused by Sunset Satan was magically fixing itself.
"We've done it!" Rainbow Dash said in victory as they returned to the throne room, "The demon is dead this time!"
"This is your world?" Flash asked to Twilight as he looked over the balcony.
"Yeah, it's quite nice when it's not attacked by the forces of darkness." She said to the human.
"I wish we could stay for a while." Said a background human, "But there's the whole can't-meet-your-counterpart rule. So we should be going."
"You're right, Silver." He said as the portal once more opened back to the now fixed high school, "We'll see you around, Twi."
"I'll see you soon, Flash." Twilight said as the portal started to close after everyone went through it, to which Flash gave her a salute before the portal dissipated before their eyes.
"So all that's left is to wait for Season 4." Pinkie Pie said after the portal vanished.
"Season 4?" Celestia asked.
"That's Pinkie for you, Celestia, always smashing the 4th wall to pieces with her nonsensical antics." Twilight said before we cut to black.