The alarm flashed red on the silver control panel in the all-white room. Tails grabbed his ears and growled in frustration while he pulled them, rustling the fresh bandages wound around his head.

"I don't believe this."

The fox sighed harshly, letting go of his ears and leaning back in his silver hover chair branded with his two-tailed symbol. He picked up his Miles Egglectrical from his lap and dragged his thumb down the screen, skimming over a blueprint of the city's electrical grid with voltage levels beside it.

"The power you generate in just five minutes could power this city for a month, but it can't be harvested because your stupid atoms have a ridiculous frequency!"

He glared up to where the eggclosure sparked with blue lightning, racing along a silver treadmill that stretched out from one wall to the other while Sonic ran at top speed inside. The teen looked bored until he noticed Tails staring and smirked.

"Sooo, can I stop running yet? Because I'm starting to feel like a hamster in a wheel, and considering you've already got me in a hamster ball, I'm wondering if you forgot my species—"

"You knew," Tails seethed, flying out of the chair with his hand clenching his Egglectrical tight.

Sonic blinked, slowing to a stop so the electricity faded and the treadmill powered down. "Knew what?"

"You knew your atoms were moving at a frequency completely different from everybody in this reality!" Tails got into Sonic's stunned face. "Because every time you jumped realities, you noticed the frequency change, didn't you?" he hissed lowly.

Sonic frowned, then threw up his hands in a shrug. "Well, I thought that might be the case, but with that big brain of yours, I figured you'd just recalibrate this little power drainer—"

"It would take weeks to ascertain your exact frequency," Tails snapped. "And that's without considering how your atoms are going to break you down to nothing if you stay in this reality for too long." He crossed his arms. "You're unsustainable as a power source."

Discomfort twisted Sonic's face and his eyes shifted aside. "Uhh," he said awkwardly, "Sorry you can't use me like a living battery?"

Tails' expression cooled. "That's okay." He leaned back from the eggclosure, smirking. "I might not be able to use your power, but with your help." His eyes narrowed. "I could use that crystal."

Sonic's face lit with surprise, but soon he grinned. "Alright!" He pumped up a fist. "Now we're talkin—"

"Don't pretend."

Sonic froze while Tails glowered, anger blazing inside him. "You don't want to find the crystal." Sonic's eyes widened. "You don't want to go home."

The hedgehog flinched and Tails smiled. "That's why you didn't run when you had the chance and why you haven't mentioned missing your friends. The only thing you seem to care about…" Curiosity entered his tone. "Is me."

Sonic's expression became serious. "You're wrong—"

"Is that why you've been trying to manipulate me?" Tails scowled. "You want to use me as a replacement for your Tails? Can't stand not having your little sidekick follow you—"

"No!"

Tails recoiled while Sonic glared, baring his canines. "Manipulating you?" he seethed through his teeth and Tails was taken aback by the genuine rage in Sonic's voice. "How could you—" He cut himself off with a hiss. "As if I'd ever manipulate my little—ugh!"

Sonic growled feral-like, glowering at the floor. However, he closed his eyes and took a deep breath. He exhaled slowly and the tension eased from his shoulders while his green eyes found Tails.

Quietly, Sonic asked, "Did it ever occur to you that maybe what I can't stand is the only family I remember—" Tails' eyes widened— "Looking at me like I'm a monster?"

Tails inhaled sharply while Sonic's face fell. "Manipulating?" he scoffed, shaking his head. "Is that what you call being friendly? Showing how much I care?"

Sonic sagged with a weight only he could see. "Fine," he exhaled a bit shakily. "Call it manipulation if you want. Do you want to know why I'm doing it? It's because I want you to like me."

Sonic's voice hardened, hurt clear in his gaze. "But you won't even give me a chance."

Guilt pricked Tails' chest and Sonic noticed, his expression softening.

"Look at me, Tails."

The fox's blue found Sonic's green, and something ached in Tails' heart at having Sonic stare at him with such gentleness.

"I'm not Sonic." Tails' heart pounded against his ribs. "At least, not the one you've been treating me like I am."

Tails' eyes flitted aside, but quickly drifted back to the hedgehog.

"And you're not my Tails." Sonic sighed. "So I'm sorry if I've been acting like you are. You just look so much like him and…"

Sonic shook his head, though he forced out a smile. "Anyway, do you think maybe you could stop…stop acting like I'm going to attack you or something?" A pleading, desperate look came over him. "Just treat me like the actual stranger you met around seven hours ago?"

Tails' fingers shifted nervously on his device, the kit looking away.

"And I'll try to do the same… Can we both try?"

Tails turned his back on Sonic, brow furrowing thoughtfully. All Sonics were liars, they shouldn't be trusted… But Sonic wasn't asking for his trust. He just wanted Tails to stop judging him for something he hadn't done…and maybe Tails could do that…

The kit looked back over his shoulder. "Okay…I'll treat you like you're a stranger." He turned around while Sonic's eyes gleamed hopefully. "But!"

He raised one finger, voice hardening. "If you want me to like you, enough with the leading questions."

Sonic winced, guilt flashing on his face.

"If you want to know something, just ask, and I might answer." Tails thought a little more and added, "Also, don't be so secretive."

Sonic's mouth drew to a line while Tails' gaze fell, hand dropping. "I've already been deceived by one Sonic."

He shook his head. "I don't need to go through that again."

The teen became sympathetic. "Oh." He nodded. "I, um, can't promise you anything—" No promises would actually be preferred considering the last time a Sonic promised him something— "But I'm going to do my best, bud—I mean, kid I just met."

Sonic flashed his teeth in a strained grin and Tails huffed. Well, the hedgehog was trying, so it would only be fair if Tails tried too.

Therefore, the fox forced the tension out of his shoulders and kept his tone even as he asked, "Okay…do you have any idea where we might find the crystal?"

Sonic's expression turned thoughtful and he rubbed his chin. "I do actually. You got a map of that island I arrived on?"

Tails quickly tapped on his Miles Egglectrical and a holographic GPS of the island sprung to life over the screen.

Sonic squinted at it, but stiffened as recognition crossed his face. "That was…Green Hill?" He grimaced. "But the ground was dry as a desert and the lakes were so polluted…"

Tails frowned. "That's because Green Hill was briefly Robotnik City Zone 1." He glowered while Sonic stared at him in shock. "But the Resistance attacked and the battle left South Island completely inhabitable, so the doctor decided to use it as a military factory station."

Sonic looked sick. "I see." He glanced at the hologram. "Well, I always arrive somewhere near the crystal…it shouldn't be any more than a hundred miles away from Green Hill."

Tails opened his hand over the hologram and the map zoomed out to show the ocean.

"Okay, so the crystal has to be on one of these islands."

Names appeared next to four smaller islands dotting the sea.

"Is there anything else you can tell me?"

Sonic shook his head. "Normally, I just run around until I hear Tails." He frowned. "Though I will warn you, things tend to get weird around the crystal. Time starts moving at a different rate, the landscape is altered…"

Tails nodded and clicked on his phone app. "In that case, I've got a call to make."

His device rang. Sonic cocked his head in interest as it rang again before it clicked and Metal Sonic appeared on the screen.

"Tails," the robot greeted. "Do you need something?"

Sonic gaped. "Metal can talk!?"

The robot's red optics slid over to the hedgehog. "Yes, and do so properly, remarkable considering who I was designed after."

Sonic's expression grew deadpan and he crossed his arms. "You know, I'd be offended, but technically you weren't based on me."

"Metal," Tails interrupted and the robot regarded him. "I need you to tell me if anything unusual, and I mean anything, has been happening within a hundred-mile radius of South Island."

"Checking…" Metal's optics flashed a soft red, gaze going blank while he mentally linked to the Robotnik databases.

The bot made a quiet whir sound and shifted slightly as he said, "Search concluded. No abnormalities detected."

Tails and Sonic's faces fell.

"However." Tails and Sonic straightened while Metal said, "There has been a slight increase in wind energy production at the power plants outside of Robotnik City Zone 34. That is normal during this time of year due to storms, but the production levels have deviated above the mean."

"Energy production?" Sonic's brow wrinkled in thought. "You know, in one reality, people were using the crystal as a power source."

Tails looked to him curiously. "You think the crystal might be behind the increase?"

Sonic shrugged. "It's possible."

Tails grinned and turned to Metal. "It looks like we have a lead on the source behind Sonic's dimension travel. Can you meet us there?"

Metal nodded. "I will arrive promptly."

The video call winked away. Tails shut off the hologram and turned to Sonic, mouth drawing to a line.

"Alright, this is how it's going to go down." Tails clicked on his wristband. "I just gave you control over the speed and direction of the eggclosure, though it will stop moving if you travel outside of my wristband's range."

Sonic slumped, groaning, "You're keeping me in the hamster ball?" He threw up his hands. "I thought you were cutting me some slack!"

Tails raised an eye. "Even if you are a stranger, you're still a super fast hedgehog who would join the Resistance the second you could, meaning you're a threat to the Robotnik Empire."

Sonic sighed, but straightened up. "Fair point."

Tails put away his Miles Egglectrical. "We can take my plane and—"

"Wait, why would we take a plane?"

Tails turned to see Sonic eyeing the eggclosure. "This thing looks like it will float, and since it can absorb all the energy I put out, it should roll as fast as I run inside it."

He gestured to the space beside him. "So wouldn't it be faster for you to come in here and let me run us over to the island?"

Tails balked. "Excuse me?"

Sonic scowled. "Hey," he huffed. "I'm not trying to trick you! Did you forget I let you put me back in this thing?"

He crossed his arms, tapping his foot impatiently. However, Tails continued staring at him and Sonic sighed, massaging his brow.

"Dude," the hedgehog said. "Stranger or not, you look a lot like my little brother."

The fox started while Sonic's eyes implored him. "I couldn't hurt you if I wanted to…" His voice softened. "You know that, right?"

Tails turned aside. This Sonic seemed to be telling the truth…and it wouldn't benefit him to attack Tails…

The kit sighed and flew over to the side of the room. "Fine."

He laid his palm on the wall. Yellow glowed under his glove before the treadmill quickly retreated into the wall and a giant shelf rolled down from the ceiling.

An assortment of tools, weapons, and equipment crowded each shelf row and Tails quickly glided over to a sleek black clip beside a bazooka. He grabbed it and flew to the eggclosure, clicking his wristband.

"What's that?" Sonic asked, scooting back while the eggclosure's roof popped open.

Tails flew over the container and hesitated, but soon dropped down inside. His arm brushed against Sonic's as his feet hit the floor and Tails reined in a flinch while the roof snapped close. He hadn't been this close to Sonic without trying to punch him or dodge his hand for…well, years.

Still, Tails kept his face neutral as he turned to the hedgehog whose thicker chest fur tickled Tails' nose. "Put this on your ear."

He offered the clip to Sonic and the teen took it, eyeing it curiously. "What is this? Some type of earpiece?"

Sonic clipped it on his right ear and Tails shook his head. "It's a monitor. If you're really hearing something when you're by a crystal, it will pick up on the vibrations entering your ears and tell me when the sound reaches your cerebral cortex."

Sonic hummed, nodding slowly. "And if you track the sound waves, you can find out where it's coming from."

A lopsided grin tilted Sonic's mouth. "That's genius, buddy!"

He moved to ruffle Tails' hair. The kit tensed, and Sonic froze. Quickly, Sonic pulled back his hand, looking away.

"Um, well, can't let Metal beat us there!" Sonic moved into a running position and winked at him. "Hold onto your seatbelt because I'm going at top speed, kid!"

Tails latched onto Sonic's shoulders and laid on his flattened quills instinctively. His blue eyes widened. He stared at his hands against blue fur. It had been years since Sonic asked him to hold on while he carried him somewhere…yet Tails hadn't hesitated to grab on.

The kit couldn't comprehend his own behavior before Sonic's legs revved into a red and blue blur and then they were blasting out the door and leaving the dark streets of City Zone 1 behind.

Tails lurched as Sonic suddenly stopped running. The fox groaned, his surroundings whirling in a mash of colors under the bright blue sky, and Tails grabbed his head to rub away the headache.

However, Sonic inhaled sharply and Tails forced his gaze up. He gasped, blue eyes locking on the field ahead.

Four jagged crystals were slanted together to form a pyramid that eclipsed the white windmills beside it, every inch of the structure sparkling in the sunlight.

"Okaaay, I'm guessing Eggman's power plants don't normally look so…" Sonic gestured at the pyramid. "That," he finished lamely.

Tails' mouth firmed to a line and he pulled out his Miles Egglectrical. The screen was black. Tails frowned.

"What? It was almost fully charged when we left."

He glared, tapping the screen, but the device stayed stubbornly off. He sighed through his nose and shoved the Egglectrical back in his fur, eyes scanning the area. Maybe Metal could take readings of this place instead—

His wristband beeped. Tails raised his arm as a blue hologram of Sonic's brain shot out above the band. Red flashed around his cerebral cortex, meaning Sonic was hearing something—

"Tails!?" Sonic shouted, and Tails jumped.

Yet he couldn't say a word before Sonic was running, the eggclosure racing towards the pyramid. Tails' eyes widened as he noticed them heading straight for a jagged wall.

"Sonic!" Tails called in alarm, fingers moving to hit the eggclosure's stop button.

Yet his fingers only brushed his wristband when they struck the wall and—

They went through the crystal like it was water. Sonic skidded to a stop and Tails gaped as he found himself on a ledge over a dark chasm. He leaned back, eyes darting up to see a thin bridge above the abyss and stretching a hundred feet away to an open door.

"Tails?" Sonic called, twisting back and forth with his ears moving every which way.

The fox gulped while the eggclosure leaned towards the abyss and quickly hit the stop button on his wristband. However, Sonic pressed his hands on the container and the eggclosure tipped towards the ledge.

"Sonic, don't—"

"Where'd you go?" Sonic asked desperately, leaning forward even more.

Tails hopped off of the teen's back and moved in front of Sonic. His heart clenched at seeing Sonic's panicked gaze, sweat coating his fur and chest rising and falling much too fast.

"Tails?" Sonic turned back and forth so quickly, his elbow nearly took out Tails' eye. "Where are you, buddy?"

The fox frowned, but swiftly ripped off his lab coat and tossed it over Sonic's face. The hedgehog made a startled noise and grabbed the coat, pulling it away.

"What the—"

"Sonic."

The hedgehog finally looked down and flinched at Tails' dark expression.

"What is wrong with you?" Tails seethed. "You almost got us killed!"

He gestured back to the abyss, and Sonic blinked, confusion dawning on his face. "Where…?"

"We're in the pyramid," Tails snapped. "You ran us in here through that wall," he pointed at it, "Which seems to be some sort of portal."

Sonic glanced at the wall, yet Tails growled and he looked back at him.

"But you didn't notice." Tails raised his wristband, pointing at the holographic brain. "Because you were too busy listening to something that isn't there."

Sonic frowned, eyeing the hologram. "What do you mean? You can see I'm hearing something—"

"In your head," Tails hissed, and Sonic's eyes widened. "You are hearing something, but there are no sound waves hitting your ears and no neurons traveling down your cochlear nerve system, which means what your hearing is—"

"Telepathy?" Sonic gasped while Tails shut off the hologram.

"Yes," Tails' voice turned to granite, "Which means it isn't your Tails speaking to you."

Sonic froze.

"That's what you thought, isn't it?" Tails scowled. "He's dead." Sonic's face went blank. "Yet when you heard his voice, you thought maybe it's him, maybe he's alive."

The kit folded his arms while Sonic looked away. "Did it ever cross your mind that this voice could just be using your memories of Tails to get you to do what it wants?"

Sonic closed his eyes, grimacing. "Yes, actually, but Tails—"

"Is dead," Tails scoffed, and a part of him knew he was going too far, yet his nerves were shot and Sonic was always such an easy target for his anger.

The hedgehog opened his eyes and sighed. "Okay, I'm sorry for getting carried away and almost dragging you off a cliff." His mouth drew to a grim line and he stared Tails down. "But you don't understand. There…" His face fell. "There wasn't a body."

Tails' breath hitched. Wasn't a body? Just how did his counterpart die?

Sonic bowed his head. "So sometimes I can't help wondering if maybe Tails isn't really gone, if he's just out…there…"

The hedgehog stilled, his ears twitching. Tails realized he was hearing the voice again as the hedgehog turned to the chasm, eyes narrowing.

"Sonic?"

The teen didn't look up while he said, "His voice is coming from down there."

Tails' brow furrowed and he glanced at the dark abyss. He couldn't see the bottom, and considering how strange this place was, maybe it didn't have one.

The kit looked up. "I can't tell how far of a drop that is without my Miles Egglectrical, but if Metal is around here, he could scan it and let us know—"

"Tails is down there," Sonic repeated firmly, his ears trained downwards. "You have to trust me—"

"No, I don't." Tails glared and Sonic started, looking up. "You've given me no reason to…and you don't have a good track record with keeping foxes alive."

Sonic's mouth dropped, the lab coat slipping out of his hand, and Tails knew his words were uncalled for, but something was wrong. The entire atmosphere in the pyramid felt wrong, and he needed Sonic to just stop and listen to him.

"I'm sorry."

Sonic glared at the chasm and Tails raised an eye. "Sorry for—"

An arm snagged around Tails and pulled him into a fluffy chest. The world started tilting and Tails' eyes widened. Yet he only glimpsed Sonic's determined expression before the hedgehog curled around him and the ground vanished under his feet.

They plummeted. Tails screamed soundlessly as the drop stole the wind from his lungs. Sonic's arms tightened around him, his heartbeat pounding under Tails' ear while the blue forcefield sparked brilliantly around them.

Tails' air ran out, but he couldn't breathe, couldn't see—

They hit the ground with a jolt and bang. Up became down while they rolled, gravel rumbling beneath them. Tails' heart was a swinging hammer in his throat as they gradually slowed to a stop.

The arms loosened around him and Tails stared blankly at the crystal stalactites branching out of the smooth crystal floor, shining faintly among the shadows.

"You okay?" Sonic asked barely audible above his heartbeat.

Tails slowly looked at him. Sonic's concerned eyes bored into his. Tails took a shuddering breath and—

Kicked Sonic's shin. The hedgehog hissed, his face screwing up with pain while he let him go. Tails jumped up as the eggclosure roof popped open and took to the air while the container snapped close.

Sonic rubbed his shin and looked to him, a question on his tongue. Yet his mouth snapped shut as he took in Tails' expression.

"You…" Tails' whole body shook with rage and adrenaline. "You moronic, impulsive, impudent, crazed rodent!"

Tails panted, feeling faint under the weight of emotions crushing his chest while he glared an inferno at the hedgehog. Sonic stared back, stunned. However, soon the teen smiled nervously.

"Uh, great Eggman impression, like scary-good Eggman impression—"

"Everything's a joke to you," Tails growled, raising his hand with his fingers poised over his wristband. "But just one click and I could electrify you into a cardiac arrest—"

"Wait, wait!" Sonic waved him down frantically. "I know that jump freaked you out, but look behind you."

Tails' eyes narrowed, yet he turned. A crystal platform hovered in the middle of the room, shimmering like a diamond caught under moonlight.

"That looks like a lift, right?"

Tails turned back and found Sonic tapping his foot restlessly, ears drooping with guilt though his expression was thoughtful.

"This place is like a puzzle…and I think I solved it," Sonic said seriously. "I mean, first Tails' voice led me into a wall that turned out to be an entrance. Then his voice led me down an abyss instead of crossing the friendly-looking bridge."

Tails scoffed. "So you're saying to reach the crystal, we have to take the less obvious route. Brilliant." His tone turned to ice. "Just brilliant."

Sonic hunched a bit, quills rising as Tails lowered his hand and flew up to the eggclosure. His cold blue eyes stared down Sonic.

"I don't care that you were right," Tails spat. "The problem is I asked you to wait and you didn't listen." Sonic wilted while Tails' teeth clenched. "I told you I couldn't trust you, and now you've proved I can't."

Sonic's eyes slanted with regret, his quills laying flat. "Tails…"

The kit spun around and flew to the platform. He touched down on the lift and it shuddered, giving a mighty groan.

"I'll get the crystal on my own," Tails said, expressionless, while the platform started rising.

Sonic's mouth fell open, shock and hurt staining his face.

"You can wait here, and perhaps, I'll come back for you."

The hedgehog reached out helplessly in the eggclosure. Funny, that was the same look Tails had wore when Sonic left him.

The kit scoffed, his namesakes swishing angrily while the platform rose higher and higher until Sonic was a dot among the darkness. Soon the shadows swept over him and Tails couldn't see anything outside of the lift. His muzzle shifted a bit worriedly when light peeked out from above.

A crystal room appeared over his head as the platform rose through a square opening and stopped, slotting itself against the corners to become part of the floor. Tails glided up, looking around and pausing when he noticed a crystal throne standing against the back wall. It was empty. Strange, he would have thought the crystal would be sitting there, but Sonic did say this pyramid was a puzzle where nothing played out as expected.

"Intruder."

Tails startled and spun around.

Metal Sonic was hovering across from him, a giant chunk of crystal sticking out of his chest and his optics white.

Tails gasped. "Metal, what happened to—"

The robot launched itself at him with a battle cry and Tails wasn't fast enough to raise his hand before a metal claw caught him by the throat. He gagged, but already he was being lobbed through the air.

Tails crashed harshly into the wall, spit erupting from his mouth while his spine rattled and screamed. Black spots splattered across his vision and Tails blinked them away only to see a metal fist right as it struck his head.

So things are really heating up now, huh? Well, I hope you all enjoyed this chapter because next time we're getting some of Darker!Sonic's backstory and it probably won't be what anyone expects ;)

Anyway, thanks for reading and commenting, all you're support is appreciated!