Some weeks pass since the defeat of the Universalamander, the Freedom Fighters continue their fight against the troublesome and tyrannical Robotnik. From meeting the strange and outlandish Verti-Cal and Horizont-Al, to saving a music hall from the music hating dictator, to even meeting the most unfriendly of Mobian Worms, the Nerbs. These adventures were fairly small and uneventful. However, on this particular day, Sally and her Freedom Fighters journeyed to Robotropolis' outskirts to find the mad doctor dumping waste to spread his deadly pollution.

Bunnie: "Sweet carrot cakes, Sally-girl. That waste's gonna cause us a whole lotta trouble if we don't deal with it."

Rotor: "She's right. If it reaches the rivers, it could make our water supply deadly to us…"

Sally: "Then we need to stop it fast. Speaking of fast…"

Sally pulls out a communicator, switching it on in order to contact their missing member, Sonic.

Sonic was elsewhere, a ways from Robotropolis, dealing with some Badniks who tried empty garbage into a field of flowers. She kicks a Caterkiller's head away as she smiles at her handiwork.

Sonic: "That's what you get for trying to dump trash. If you're going to do that, dump it somewhere else, or else I take out the trash."

Putting aside the lame quip, Sonic hears her communicator go off, signaling her of some trouble going down at Robotropolis.

Sonic: "Seems like Sally and the others are gonna need a little hand from the ol' hedgehog gal herself. Don't worry guys, I'm on my way!"

She dashes off towards the direction of Robotropolis, running as fast as she could. However, as she ran, a sudden portal opened in front of her, causing her to trip into it.

Sonic: "Wh-Whoa!"

She starts rolling out of control before coming to a stop through another portal, landing on some dirt.

Sonic: "Of all the lousy, no good… Huh?"

As she rubbed her head in mild irritation, she looks up to see her surroundings. It was… the Great Forest it looked like, but there was now an unfamiliar tower. From a distance, she read the sign saying 'Veterinary Clinic', but at the top of the tower was an 'R' symbol.

Sonic: "Robotnik? A vet? Okay… My hedgehog senses are tingling and they are telling me I'm not in Mobius anymore… But it feels like Mobius… I need answers and I see no better source than the doctor him-"

As she ran towards the tower with fast speed, she crashes into something- or rather, someone.

Sonic: "...-self… Okay, I'm getting real sick of having my butt plastered to the dirt! What did I run into now!?"

She stands back up in a huff, but her anger turned into confusion quick as she saw another blue hedgehog, much like herself, but instead wore a black leather jacket, a pair of sunglasses, and - above all - was a boy instead of a girl. The shape of his spines was undeniably similar to her own.

Sonic?: "Ugh… Great. Who's the wise guy who crashed into me?"

The other Sonic was equally peeved by the sudden crashing, rubbing his own head, before he spotted the girl Sonic.

Sonic?: "Great. First a goodie two shoes Sonic, now a girly girl Sonic."

Sonic: "A what Sonic, punk? Wanna run that by me again?"

Sonic?: "Sure, toots. Allow me to just give ya the short version!"

The leather jacket Sonic lunges at female Sonic, hitting her with a speedy Spin Dash that knocks her to a tree. The other Sonic stands back up straight as he smiles at his handiwork.

Sonic?: "Heh. Maybe you're not as tough as the other guy. Gotta say, I'm in a real rotten mood right now; some bozo from opposite land decides to come into my town, ruin my day, and puts me in a trap by that good ol' doctor in the tower back there. I barely escape, and now some dame's come into my house? Just my luck."

Sonic: "Yeah. And this 'dame' ain't hear no bell either!"

The punk Sonic get hit by a set of shoes to his stomach, knocking him off his feet as Sonic herself stood back up. The other Sonic backflips to his feet before glaring at his female counterpart.

Sonic: "So whose house did I enter anyway? If this isn't my Mobius then what Mobius am I in?"

Sonic?: "Tch. Rather than give ya the whole wringamaroll I gave the other guy, how about the condensed version? See, you're in a Mobius where wrong is right and right is wrong. Where freedom is overrated here but we do love beatin' up the punks around here. Includin' messing with good ol' Doctor Kintobor."

Sonic: "Kintobor? Robotnik backwards? Does that make you… Cinos?"

Cinos: "What!? No you dumb broad! You can call me 'Anti-Sonic'. Because I'm the opposite of any goody-goody Sonic. And what I say goes."

Sonic: "Really? Sounds like you need to be brought down a few pegs."

Anti-Sonic: "Heh. Go ahead and try it then, if you can keep up!"

The two begin to rev up a Spin Dash before launching at each other, clashing their attacks before splitting off, uncurling as Sonic ran at Anti-Sonic, slamming an uppercut under his chin. It connects and angers the other hedgehog before punches back, slamming a fist right on the other Sonic's right cheek. Their attacks were swift, either being blocked or dodged; any hit that landed would be quickly retaliated. Anti-Sonic lands low sweep under Sonic's feet before going into a breakdance to kick her back. He takes a pause as he catches his breath.

Anti-Sonic: "Whew… Not bad, toots. You're actually a lot tougher than ya look. Though, I guess lookin' like me would make ya look tough."

He says before rubbing a bit of sweat off his head as Sonic stood back up.

Sonic: "Says the wannabe blue hedgehog. It takes way more than some leather and a pair of sunglasses to be tough."

Anti-Sonic: "Then how about a posse then?"

Sonic: "A wha…?"

As Sonic contemplates what she meant, she is hit on the head by a baseball bat, sending her to the nearest tree with her ears ringing. She looks up, grunting as she is suddenly surrounded by leather wearing copies of her friends - no doubt Anti-Sonic's version of the Freedom Fighters.

Anti-Sally: "Seriously? You're having a rough time with this wuss?"

Anti-Sonic: "Hey, it's 'me'. Of course 'I'm' pretty tough."

Anti-Tails: "Stay down if you know what's good for you, you blue vermin!"

Sonic didn't exactly listen, partially due to the ringing still going on and partially because she was never one to do as she was told, unless there was a good enough reason; she stood up, holding onto the tree behind her as she glared at the Anti-Freedom Fighters, Anti-Sonic approaching her.

Anti-Sonic: "Listen, I'll admit that I'm a bit of a rough guy at times, but I can be nice too. Why not join my gang? Two hedgehogs, taking Mobius for ourselves? I can even offer you…"

Anti-Sonic reached out, going for Sonic's chest as her eyes widened.

Anti-Sonic: "...a good time."

Sonic: "...Screw…"

Within a fraction of a second, Sonic slams a fist right on Anti-Sonic's face; there was enough force behind the punch that the squad heard the sound of bone cracking as Anti-Sonic's sunglasses broke. He flew backwards, crashing into Anti-Sally, as his shades fell to the ground. As the Anti-Freedom Fighters charged towards her, she quickly placed her hands on the tree behind her as she started to use her feet to kick up a large cloud of dust. This blinded the group as they ran into and started beating each other up. By the time the dust cloud had vanished, Sonic was gone.

Anti-Rotor: "Wait… Where'd she go?"

Anti-Sally: "Urgh… You idiots! She's getting away!"

Sonic was rushing her way down the path, hoping to run into some kind of way back to Mobius. To her luck, she found a portal open up and allowed her to exit through it. She lands on some kind of pavement as she takes a deep breath, on her hands and knees as she looked back at the portal, which had shifted to another location in the preview.

Sonic: "...S-Screw that place… Just… screw that place…"

No witty commentary, no real victory. Just a girl who was just done with the day. She made her way around the pavement, retracing her steps before eventually arriving to what she assumed to be her Mobius - numbered 63P.

Just on the outskirts of Robotropolis, Sally and her friends were under siege as Robotnik had spotted them and had his Swatbots, armed with sludge cannons, to fire and down them in sewage.

Robotnik: "Give up, Freedom Fighters! Sonic will be too late to save you and Mobius will be my polluted paradise! Everyone will be forced to become robots just to survive!"

As Robotnik laughs, a portal opens as Sonic lands, looking particularly peeved.

Robotnik: "Wha-!? Sonic the Hedgehog! So you did make it! Well, no matter… You cannot defeat-"

Rather than just let Robotnik finish his monologue, Sonic jumps up to his Egg Mobile and delivers a kick so hard, it sends the doctor flying right in the direction of his waste disposal plant.

Robotnik: "YOU DIDN'T LET ME FINish!..."

He crashes into his waste disposal plant, causing it to explode, essentially solving that problem in an instant. The Swatbots held their weapons, but were more so hiding behind them; when Sonic gave them a very fierce glare, they collectively and wordlessly said 'screw it', dropped their weapons, and retreated back to Robotropolis. Sally, a bit relieved to see Sonic, noticed something off and approached her, as did the rest of their friends.

Sally: "Sonic. You made it! You… uh… Are you okay?"

Sonic: "...Yeah. Just had a rough trip."

Tails: "A rough trip? What do you mean?"

Sonic: "I'll write a report and all, but… I'd rather not talk about it… Not now anyway."

The others wanted to pry a bit, but Bunnie, acting like the mother of the group, stepped in.

Bunnie: "'Ah say that's mighty fine, Sonic. Yer lookin' a bit stressed so how 'bout we just go celebrate our win, huh?"

Sonic looks to Bunnie, then smiles. The group start to head back to Knothole, with Rotor offering to just build a device to clean out the waste once they got home. Sonic looked up to the skies, wondering - hoping - if that would be her last encounter with that other Sonic…

Back on Anti-Mobius, Anti-Sonic walked up to his sunglasses, which now had broken frames and lenses. Completely ruined… Crushing them in anger, he growled.

Anti-Sonic: "Oh now you messed with the wrong hedgehog, you stupid broad… Next time I see you, I'm gonna break more than your bones… That's a promise…"