Sonic Adventure 2 This is an alternate version of Sonic Adventure 2, which I did as a writing exercise. The plot differs extremely from the established storyline, but it did for the STC Sonic Adventure as well (I haven't played the game, so the characters may not all be in character.) Most characters are © Sega.

Epilogue:

From the scattered cluster of the ARK a tiny, pencil-like craft dropped away to Mobius. Robotnik and Tekno had patched it up enough for the engines to cushion the fall, and had let the planet's gravity do the rest.
The survivors had gathered on the passenger deck, which was covered by rows and rows of cinema-like chairs. All was quiet, everyone lost in their own thoughts. Sonic sat by the window. He watched the planet plunging closer, the planet Shadow had died to save.
Shadow hadn't even known it properly. He had spent all his life being either tested or hunted, and had never had time to see the world's good side. Sonic gritted his teeth. When he got back, he would see to it that his rival got a decent memorial.
He would also do his best to get rid of G.U.N., the cause of all Shadow's misery.
Sonic felt sick inside. He hadn't known death at all until a short time ago, now he was losing more and more. At least now the Ultimate Life Form would be with his best friend.
The Ultimate Life Form. Sonic wasn't sure how he felt about that. Shadow had been so like him, it was uncanny.
Could Gerald's grandson have inadvertently recreated his experiment? But Sonic had been fast naturally, before the Chaos accident. Of course, all that had made Shadow ultimate, according to Gerald, was Chaos manipulation. Maybe Shadow being super-fast was an unintentional bonus.
Questions and answers raced in and out of Sonic's head, forming endless possibilities and semi-conclusions. Sonic agitatedly shook his head, trying to shut them up.
Whatever was going on, Porker could deal with it, he loved that sort of thing. Sonic had more important stuff to do.

Rouge sat at the back, thoughtfully. G.U.N. would probably be searching for her now, as she hadn't reported once since her mission began. Well, stuff them. Rouge the Bat was no one's spy. She would continue to steal what she wanted, and the first thing to go was Knuckles' Emerald.
She scanned the deck, and saw Knuckles talking to Amy. He brushed a long red spine out of his face, and handed over a small bag of Chaos Emeralds to Sonic, who had just walked up. Rouge guiltily fingered the ruby she'd taken.
Sonic was shaking his head. "No, it's fine." Knuckles said. "The Master Emerald can power the Island by itself. You and Porker can finish your tests without me being involved. I want them back, though." Knuckles stood up and made for the door at the back.
Knuckles would have to wait longer then he thought, then, to get this weird Island flying. Rouge felt another twinge of guilt; Knuckles had obviously worked hard to keep his Emerald. The echidna wasn't that bad, really, when he was on your side. Maybe she shouldn't.
Rouge stopped her thoughts dead. Why was she sympathising with her enemy? She hadn't been trained to feel sorry for people; she had been trained to fight and survive.
No, she would get the Master Emerald, if it were the last thing she did.

Shortfuse the Squirrel gripped the seat in front, and the maroon velvet back twisted and buckled under his enhanced strength. They had saved the world. The enormity of the fact overwhelmed him, that he was partly responsible for millions of lives.
Of course, he'd also saved Robotnik's life; without Shortfuse the madman would have been obliterated by the Eclipse Cannon. That would normally have made Shorty curse, but now he smiled. Robotnik was now in his debt, and although the mutant would never admit it.
Robotnik had come close, though. Frighteningly close. If it hadn't been for Shadow.
Shortfuse stared out of the window, but saw no sign of the hedgehog. He wasn't especially sad; he hadn't known him. Something else, however, made him clench his fists and grit his teeth.
Shadow was a twisted genetic experiment, designed to destroy the world. If someone like that could turn out good, then surely Shortfuse could as well. It didn't matter if he owed his existence to Robotnik, he would make Robotnik regret it more then him. Shortfuse smiled.
And as for Shadow. Well, if the hedgehog was anything like Shorty's little experience of Sonic, then there was a chance he would escape from whatever the situation, even re-entry.

Hundreds of miles away, towards the north of Mobius, an old fox sat, moonlight outlining the dew on his grassy carpet. He stared at the infinite stars, which stared back down on him. A flash of jade streaked across the heavens, chasing the moon into the horizon, then disappeared.