So this has been kicking about well started but in random chunks for some time know - first I was holding off to check Forces didn't contradict anything I was planning and then to check Plus didn't and then I sort of drifted off. But anyway. Well underway again.

No real 'version of reality' notes to add this time - except of course all of old 16bit games used 'Robotnik' not Eggman being UKSide, but I've come around... ;-) I'm assuming from trailers etc that the sequence is S3&K, Chaotix, Mania, Forces (from younger Sonic's viewpoint anyway), ManiaPlus.

Sonic skidded to a halt, cradling two full bags of still-steaming food in his arms to stop the whole lot being propelled onto the ground by the abrupt stop.

"Tails?"

The fox was nowhere in sight although the Tornado was still here, beneath its temporary wooden shelter outside the cliffside structure that was half cave, half ruin and, at the moment anyway, half finished. A pile of debris and broken objects lay outside – most of them ancient but utterly mundane, bowls and cups and broken tools. Sonic gave the heap a scowl as he passed, having spent a boring morning helping drag most of it outside when Tails decided that the place would make the ideal spot for the workshop he'd been talking about building.

Sonic was so-so about the idea – who wanted to stay in one place? But Tails was excited by it and so he'd helped. He did have to admit the fox was accumulating a huge amount of stuff to go along with his growing technical skill and needed somewhere more substantial to keep it and work on it than the month-here-month-there way they'd been living as they rambled around the planet.

"We can still explore, Sonic," Tails has argued. "We just don't have to cart all this with us! I can build cool things so we can explore even better. It's not like you have to stay here all the time or anything." Sonic had smiled and agreed because he could seldom say no to Tails and because that 'you don't have to stay' had made him pull Tails over to ruffle his cow-lick. "Course we can still explore, buddy. It's what we do!"

Now Sonic lowered the bags of food to swing loosely from one hand and stuck his head inside the cave-or-door-or-whatever. A string of aerials had been wedged into the cliffside above it and Sonic glanced up as he passed under them, since they looked none too secure.

"Tails? I picked up lunch!"

"Sonic! Over here!"

Sonic crossed the chamber cautiously, the floor was still littered with boxes and clutter not yet removed or sorted or stored. Some of it Tails had acquired himself, much was salvaged from Eggman's now destroyed labs and ships. Sonic had expected to find Tails in the process of sorting or setting it up but instead the fox was perched on top of a stool staring at a handheld screen instead.

He reached absently for the meal as Sonic deposited it on the table and returned his attention to the purple smear across the screen.

Sonic frowned at it.

"Did it get broken in the move? That sucks."

Tails shook his head and swallowed a large mouthful. "Not broken, that's what it's really reading."

Sonic started in on his own chilli-dog.

"Mmm. So what is it? Where is it?"

"I don't know." Tails put down his burger and tapped something on the screen, pulling up a map overlay. "I mean I don't know what it is. I know where. I think."

Sonic surveyed the map. "That's a big load of middle-of-nowhere ocean!"

"Yeah," Tails agreed. There's not much out there, not even any shipping routes. But the energy signal's not coming from the surface." He hesitated and frowned uncertainly. "It reads like it's a good ten thousand foot up."

Sonic grinned, his curiosity well and truly piqued. "So a mystery mountain in the ocean or something flying? Eggman? You'd think he'd know when to quit!"

Tails shrugged. "No idea. I did wonder if it could be Knuckles' island. That was plenty weird enough but this looks new. I bet Eggman's picked up that signal too though."

Sonic bounced on his toes, gulping the rest of his meal in two bites. "So let's go find out!"

Tails pulled his attention from the screen, glanced around the half finished workshop then back at Sonic and grinned.

"Right now?"

"Course!"

Tails launched straight from his stool into mid-air and shot past Sonic. "First one to the Tornado's a big loser then!"

Sonic was on his heels in a moment, and despite laughter and having to navigate the article-strewn floor arrived at the aircraft in the same breath as the fox who stuck his tongue out.

"I totally made it first this time."

Sonic eyed him with mock suspicion. "I demand a photo finish." But he couldn't maintain the pose for more that a few seconds before laughing

"Let's go."

Tails nodded and went about starting up the aircraft.

"How far is it?" Sonic asked over the sound of the engine warming up.

"Not far," Tails called back. "An hour or two."

Sonic grimaced. That did sound like a long time to him. As soon as they were airborne and cruising he was casting about for conversation and they tossed theories back and forth.

Whether Eggman could already have recovered enough resources to build something capable of turning out that much energy and flying that high so quickly. Whether finding something powerful enough to put out that much energy was why he'd been able to. Whether it could be something to do with that weird giant Chaos Emerald that Knuckles called the Master Emerald, or something else to do with the Floating Island. They'd left it almost as much of a mystery as they'd found it after all and its guardian had been particularly unforthcoming in terms of any real information about it.

It was a little over an hour and a half when the first of their questions was answered as the silhouette of the Floating Island came into view against the endless blue horizon. Sonic frowned at it, realising rather belatedly that although they'd parted from Knuckles on reasonably good terms, he was far from sure the echidna would actually welcome them back as either visitors or would-be allies against any new threat.

Tails brought them in over the Island, his attention flicking from the tracker to the terrain.

"I'm sure we shouldn't have found the place this easily. Knuckles must have it out here in the middle of nowhere for a reason. But the signal's enormous. Whatever it is. D'you think Knuckles knows?"

Sonic shrugged, deciding not to share his misgiving about their potential welcome or lack thereof. "I bet he knows most things that go on on this island of his. Still... If it's that big.. Even if it isn't Eggman causing it the odds of him picking up the signal too... Can't hurt to make sure can it?"

"There, Sonic!" Tails yelled but Sonic had already seen them – a cluster of Egg Robos. He couldn't see what they were up to and Tails was already pulling up to miss them.

"I'm going for a closer look!" Sonic yelled against the wind and leapt from the wing straight into a run. He'd intended to attack at once, but skidded to a stop when he realised they were paying no attention to him whatsoever.

"Hey," he peered up at them. "A hedgehog could be insulted y'know!"

Over the clatter the Robos were making, Sonic didn't heard Tails touch down beside him until he spoke up.

"What's going on? Why aren't they attacking?"

Sonic shrugged. "Busy with something else. What d'you say? We try smashing a few, see if that gets their attention?"

Before he could begin to do so a rumble from above marked the arrival of a huge, claw-like digging machine which plunged into the earth as though there was no resistance at all and rose again almost at once, clutching a boulder-sized chunk of rock and earth and rising and accelerating away from then with the Egg Robos in a gaggle around it.

Tails glanced at his tracker. "That's it! Whatever they've got there in the source of the signal!"

Sonic saw no need to answer, he was already running. He couldn't reach the ship dangling the claw but leapt at the appendage itself which only made it sway dangerously. Tails swerved in mid-air to avoid it.

"Woah!" Sonic leapt aside as the swinging rock whiplashed crazily beneath the ship. "Okay, bad plan! Tails, can you give me a lift? We need to get this thing from above."

Tails swooped in and hoisted him into the air as the Robos rocketed out from under the cliff and towards the jungle.

"Knuckles is down there!" Tails called out suddenly. Sonic looked round from where he was trying to pick the best spot to leap at the claw and saw Tails was right. Knuckles was watching the oncoming Robos, poised to fight, fists raised.

Sonic had been on the wrong end of that stance all too recently and it was clear Knuckles had no intention of budging even if he had to take on the whole mob of oncoming attackers.

He looked up at the swinging chunk of rock and Sonic couldn't work out whether Knuckles actually thought he could grab and hold it or if he'd just misjudged the angle of approach but either way the chunk of rock smashed into him with a sickening crunch that sent him flying off his feet to land motionless on his back.

"Knuckles!" Tails yelled, sounding shocked and almost losing his grip on Sonic.

Sonic couldn't blame him, the blow had looked more than enough to be fatal and Knuckles wasn't moving. Sonic twisted free of Tails' grip and landed one strike on the nearest Robo before joining Tails at Knuckles' side. He was alive, Sonic realised with instant relief, his eyelids flickering on the edge of consciousness, no blood, no visibly broken bones.

"Stay with him," Sonic told Tails, "I'll-"

But the Robos had also stopped and Sonic hesitated, crouching himself preparing to spindash anything that thought it could come back for another go. He glanced at the others, saw Tails also readying himself to attack, Knuckles now struggling to sit up, propped himself on his elbows, glassy-eyed but still fighting to focus on the threat at hand.

And then the world… shifted. Blurring, spinning, colours and sound in twisting confusion and they were tumbling, twirling in the air.