Spike had disappeared. Everyone who knew anything about him was asked to search for him in pairs. Well, at least everyone who could search for him. The week before, Rarity broke her ankle. A wound Twilight was able to fix, but it would still be throbbing for a while. There weren't a whole hoard of witnesses to the event… but there was Spike. And Rarity asked him not to talk to their friends about it. Spike knew something about the accident, and he was going to do something about it.
That was Twilight's theory, but at the moment that was all it was. Sonic and Dash were acting on that theory. Rarity said that the accident happened near Lava springs, from a boulder breaking on a stalagmite a Fragment of which ended up hurting Rarity. Rainbow saw where it happened; the big rocks near the stalagmite on the north end of the pool were the giveaway. Sonic hopped on the rocks to cross the lava (because he can't fly in his normal state) and Dash noticed a movement. From the shadows came that guy that attacked Shining Armor! What was his name? Mephiles! And he had something in his hand. Upon closer inspection she realized it was Spike, who was unconscious and beaten badly.
"Hello, Sonic the Hedgehog," Mephiles said. "What are you feeling now?"
"It was you!" Sonic said softly. "You broke Rarity's Leg! You beat Spike into this!" He gestured to Spike's limp form. "Why do you have to Kill Everyone?!"
"I think… Therefore I am." Mephiles responded. "For me it's more Complex, I Destroy… Therefore I am. All I could ever be is the Dark Side of Destruction, where Iblis is the Light. And soon enough, I will have all the power I need to become whole with Iblis again." Mephiles sank into Spike's shadow. Just as the shadow of the armor disappeared where the Scepter landed, Spike's shadow was absorbed by Mephiles. Out of the fog Mephiles created, a figure appeared. Dash knew it was Mephiles this time, even though it looked like Spike without his mouth in black and white. It kept growing, however. When it finally stopped Dash was having a flashback to Spikezilla, nothing worked against it, until Spike remembered Rarity. Last time, she tried to fight Spike, whose weakness was Rarity. This time she was fighting Mephiles, who didn't have anything to use against him.
Dash was trying to figure out what to do, when Mephiles let out a roar. He swung his fist downward and Dash couldn't move, then she realized that Sonic was the target. She jumped and pushed Sonic out of the way. That's when everything went dark.
Sonic"Dash!" Sonic screamed. He scrambled to his feet and ran to her limp body, not dead, just unconscious. But she was in bad shape, some of her bones were broken, but they weren't major necessities, a couple of ribs and a wing, but that was it. Even as mildly injured as she was, Sonic almost felt hopelessness for her to survive, at least while Mephiles was still here.
It's time to release the Power confined in your DNA. He heard Chaos say. It's time to unleash Madness.
Sonic's mind was aware of what he was doing after that. But he was not in control. The transformation happened first. His fur went black, it would've been darker if that were possible, it was definitely darker than Shadow's. His shoulder blades began to grow little bumps extending until he had fully developed wings, like an angel. Every feather was black, hard as metal, and so sharp it could cut through bone without any resistance. The wings themselves were twenty feet long… each. The most disturbing thing he saw in himself was his eyes. They had become red, like Shadow's, but there was nothing in them but pure insanity… no… that wasn't the word… it was… Madness.
The Madness made Sonic turn his attention to Mephiles as an Insane Grin spread across his face. Mephiles acted like this was nothing to be afraid of. He raised his arm and tried to bring it down on Sonic. Sonic just raised his hand and caught the arm that would've sent him down into a crater, and it offered no resistance.
Mephiles looked a little less confident now, but what threw every shred of certainty of his capability out the window was when Sonic grabbed the arm, lifted Mephiles off the ground with no possible leverage, and threw him so hard he orbited the planet, going further and further out until he was flying into space in twenty seconds. Sonic followed so quickly it was if he were made of tachyons, which are, for those who don't know, theoretical particles that can move faster than 299, 792,458 meters per second.
Sonic showed up behind Mephiles, and punched him into the surface of the moon. Sonic reached the surface just as Mephiles made contact. When Mephiles regained his balance, sonic came up and threw punches and kicks all over him so fast, if time slowed down around you, you'd be able to see Sonic's attacks going as fast as they normally would. Finally Sonic stopped holding back.
"Enforce the Law!" he yelled as a ball of evening blue energy formed in his hands. Eventually (and by that I mean in about two seconds), the energy sphere became as big as the moon. He threw the orb at Mephiles who was thrown into a crash course with the sun. It took about a minute before Mephiles ran into Sonic, Just outside the Gravity field of the sun.
"The bigger you are, the faster you burn," was what Sonic said before he threw Mephiles into the gravity field. "Let Chaos Rein!" a blade of blood red energy formed in Sonic's hand and he brought it down on Mephiles, increasing his speed towards his death. About five feet from the surface, Mephiles disintegrated into particles and those were destroyed as they reached the sun.
There was fear on Mephiles' face as he realized that there would be no returning this time. There was no possible way for him to avoid being completely destroyed by the light of the sun. But Sonic… his face was the same Madman's Smile as at the start of the fight. His wings shining with the reflected light of the sun.
Rainbow DashPrincess Celestia had brought Spike and an unconscious Rainbow to Canterlot Castle. They were healed of their wounds and were waiting for Sonic to return. Celestia felt something coming on a crash course with the castle. She went outside and used her magic to slow it down before it was teleported to the balcony. It was Sonic, as Dash had guessed. But he had wings.
When Celestia went to touch them they burst into a flurry of feathers, without any skin, flesh or bone connected to them. Rainbow saw the entire fight through the haze of her unconsciousness. She never thought she'd ever see Sonic so insane. It scared her. And the fear on Mephiles' face as he went into the sun… it couldn't have been that sonic wanted to do that. She caught a feather in her hoof. Just as it landed, Amy came rushing onto the Balcony.
"Sonic!" she ran up and embraced the one she was searching for, making Dash a little jealous. "Sonic, what happened!?" she turned to Dash, and with a raspy voice, made less bearable with her anguish, she said, "Who did this to him!?"
Dash didn't notice the colt walk out onto the balcony, or Rarity moving to a still unconscious Spike. The tears in her eyes blurred her vision too much, as she recounted everything that happened during the fight with Mephiles.
"I don't know why he would do this," Dash said. "I'm so sorry."
Amy looked like she had been caught in a no hope situation that would've killed her, but she survived going through it. She just said five words to Sonic before Applecore put a hoof around her and guided her to the exit.
"Sonic. What have you become?"
Funny thing, Dash was going to ask the same question.