Spike the dragon was walking through the streets of the Crystal Empire. Ponies see him come by their stands as he passes by. Fans asking for autographs were answered with silence as Spike walked with his head down. He couldn't believe what has become of his poor sister. In fact, when he walked over to the gates, he started to shed a tear from his left eye, wondering what horrible things Cosmos is making Twilight do.
Back at the Canterlot Castle....
Twilight slammed her back on the wall on her right on purpose to get the creature inside of her head, out of her head. And Twilight was mad, VERY mad. So mad, she put both her hooves on the top of her head. "GRRRRRAAAAGGGHHHH! Get. Out. Of. My. Head!" Twilight shouted as she slapped her face with her right hoof and then her left. "You made me do all sorts of terrible things! Making me yell at Spike! Sucker-punching AJ into a cage and leave her there in the Canterlot Archives! Use my body and my magic to make Celestia your puppet while also making Luna your puppet, too! You made me tangle AppleBloom, Sweetie Belle, and Scootaloo in vines, and then lock them up along with Capper with AJ! Not to mention you made me turn Zecora and Big Mac your puppets as well! And you even put me in a stupid dress with my mane stuck as in Afro! Why can't you just stop?! Twilight screamed as she put her hooves on her eyes as well as let a few tears fall down.
Cosmos's voice actor, the same as The Mane-iac.
"Well, that's easy, my puppet," Cosmos began as she popped out of Twilight's horn like a shadow, while also making Twilight move her head on her free will to look at the evil creature while she has hooves up at her face. "I won't stop until I rule all of Equestria! Well, maybe not the Dragon Lands, but you know what I mean! Now, let's see," she begins once more while she starts lifting up her right talon to lift Twilight into the air. Then, with a snap of her left fingers, Cosmos popped some clothes into view on her left side.
She strapped a saddle to Twilight's back, pulled some gloves up her forearms, pulled two pairs of fishnet socks up her legs, strapped white laces to hold the socks up, made her tail all poofy, made two sides of her hair the same length, and put dancing shoes on her hooves with a snap of her right fingers. Next, Cosmos snapped her left fingers and put a ring with a diamond on Twilight's horn, placed a heart-shaped tiara onto her head, and finally places a metal bar with straps into Twilight's mouth.
"Now, let's do something about that green raging goliath you hold within you, shall we?" Cosmos said as she squinted her pink eyes closer.
Twilight perked up. "No. No, no. You wouldn't," Twilight said in despair.
"Oh, I would, haha," Cosmos laughed and then pulled her body back, and then shot like a jet into Twilight's chest.
Twilight stood on her two hooves and placed her front hooves on her chest after the impact. Then, she pulled them away and looked at her right hoof. She grunts painfully as her hoof shifted into a paw and sprouted four claws simultaneously and swelled up with huge muscles. The shoe became a fingerless glove. Then, she grunts painfully once again as the same thing happened to her left hoof. Twilight pulled her chest back as she felt abs coming in. Then, two pecs appeared and pulled Twilight to the ground as she groaned as her mouth expanded and her wings turned into bat wings, and her tail growing longer.
The transformation stops when Twilight was hugging herself to keep Cosmos from turning her into Spark. "I-I won't let you hurt anypony else!" Twilight shouted in pain as she was almost close to become her alter ego.
"I doubt that. When I reach the Crystal Empire, I'll make sure to say "hi" to the dragon you care so much," Cosmos chuckled.
Twilight perks up. "I swear, if you hurt him in any way, and when I get full control of my body, I'll personally make sure you get hanged!" She said as her skin was still the same. But, still has her muscled parts.
"Oh, I wouldn't dream of it," Cosmos said snarky.
Then, Twilight screamed in pain as her brain started to shrink and her skin and fur turn green as well as her mane turning black. After one last grunt in pain, the transformation was complete, and Cosmos was in control now once more.
"Now then, *pant* let's pay your brother's family, *pant* your friends, *pant* the citizens of the Crystal Empire, *pant* and that dragon a visit," she said as she was panting from turning Twilight into her alter ego and controlling her mind once more.
Inside Spark's possessed mind...
"NOOOOOOOOO!" Twilight screamed inside the darkest pit of her mind as she was in chains, and the same clothes Cosmos has put on her.
Then, using Twilight's mutated body, she jumped out of the Canterlot Castle and through the sky and landed on the ground. She kept doing that until finally she made it to the Crystal Empire.
Meanwhile, at the gates...
Spike looked above through the clouds as he saw an object coming through the clouds and impacted the ground. When he squinted his eyes, he saw that the figure was green and had pink eyes. It was Twilight in her Spark form, but then he remembered what Discord said. "Anycreature with pink eyes and slits means that they're possessed by Cosmos," Discord's voice was heard as Spike remembered what he said.
"What do you want Cosmos?" Spike asked with defiance.
"Oh, come on, Spike, it's me, Twilight," Cosmos Twilight said as she moved her left paw onto her chest.
"Twilight would never have pink eyes unless she got something in her eyes, Cosmos. And she can only say Hulklight and Spark while in that form," Spike said as he crossed his arms.
"Well, it was worth a shot," Cosmos Twilight said as she took her paw off of her chest and kept it in the air for a little.
"I know you're here to find another star fragment and another innocent soul to possess, and I'll let you know that it ain't gonna be me!" Spike shouted.
"Fine how about this: If you can find me the last star key, and find someone to possess so that I may complete my spell to release my body from my prison, I'll give you back your sister," Cosmos Twilight said. "But only if my spell is complete will I give her back. "Mind and body, and all that other stuff," she said as she used her hoof to make gestures. "Do we have a deal?" She said as she kept her paw up in the air.
Spike looks at his possessed sister's paw, then stares into his sister's possessed eyes. He lifted his left paw and grabbed her paw. "Deal!" He said calmly but firm as he shook her paw twice. He lets go, but then he starts to speak once again. "But, can I at least talk to her?" He said as he kept his arms at his side.
Cosmos rolled her eyes to the left and then stares at him. "Fine. But only for 5 minutes," she said.
Then, Twilight's body started shrinking, and with that, Spike heard Twilight's voice return as she grunted in pain. As the transformation was completed, Twilight looks up with her normal eye style and normal eye color. Her eyes started watering. "Spike!" Twilight shouted as she lunged forward and grabbed Spike. Spike didn't expect it, but, he got what he wanted, even if it was only for 5 minutes. He hugged her to calm her down while she cried.
"I'm so sorry for yelling at you, Spike!" Twilight screamed in pain and sadness.
"Don't worry, Twilight, it's not your fault. It's Cosmos's fault that she made you do that, as well as other things," Spike reassured her as he waves his left paw through Twilight's shoulder blades.
"*Sniff* I know. But what about you? You made a deal with an evil being, who has possessed me, to find another key fragment and another host for her to control," Twilight said as she held Spike's shoulders.
"I know that, Twilight. But it's the only way to bring you back. Plus, I already know the perfect pony for Cosmos," Spike said as he pointed at the sky with his right finger.
"Who Spike?" She asked.
Spike used his right paw to notify her to come closer to lend him her ear. Twilight did what Spike told her to do and him her left ear. Spike started whispering one word into Twilight's ear.
Twilight perked up. Then she looked at him. "Her? Really?"
"Yep. She deserves to be the one who will be the last host for Cosmos after what she did to you," Spike pointed out with his right finger.
"But-" Twilight stops when she perked up as she felt pain in her chest, followed by a metamorphosis back into Spark. Twilight's eyes opened up, but they weren't Twilight's.
"Great idea, Spike, haha! She'll never know what hit her!" Cosmos Spark said as she lifted her left and turned it into a fist. "But first, we need a plan to lure her to Canterlot Castle. Any ideas?" She said as she pointed her left finger on her chin.
Spike started thinking for a moment. Then, he perked up as he came up with one. "I have a plan," Spike said as he lifted his right finger up. "Here's how it goes," Spike started as he lifted both his paws up.