Written for the Kelviniana forum Dark Waters of Halloween challenge.

Disclaimer: I don't own the characters. SEGA does.

.w.

Chaos was subdued, the Egg Carrier II lay in ruins, Eggman fled with Sonic hot on his heels. Now that the danger was no longer looming over the world, the heroes parted once again. Amy Rose was evacuated to Central City among civilians who managed to survive the cataclysm. Given Station Square's current state, a lot of time would pass before she and others could return home.

Most of the city was underwater, and it didn't look as if the situation was going to change anytime soon.

An intricate network of tiny rivers that criss-crossed the jungle in the Mystic Ruins went wild. Every single spring exceeded its powers, as if determined to flood the whole world all by itself. Finding a dry place had been just an extremely hard task several days before; now it was plainly impossible.

Tails was lucky to have his workshop on top of a hill. Meanwhile, Big would have to look for another place to live - unless he cherished the idea of having a knee-deep pool inside his hut.

Eggman's base was on the brink of much more prominent suffering. Located in a lowland area, with an exceptionally rich river embracing it, it soon found itself in the middle of a quickly widening and deepening lake. While the central tower had nothing to worry about, the circular formation at the foot of it was going to disappear under the surface soon enough.

Some doors on the lower levels had been wide open since Eggman's departure, and the passages behind them were already full to the ceiling. Other doors were damaged after a couple of hedgehogs went through them, and the water was leaking through the cracks.

Occasional, agonizing sparks of electricity were surging through the base. One of them, desperate to escape its fate, headed down a route it wasn't supposed to enter and ended up inside a green hexagonal platform on one of the lower levels of the base. Surprising even itself, it didn't simply disperse; instead, it kept growing until it finally imploded, hugging a dark frame on top of the very same platform with a spectral cloud of blindingly white dots. In a matter of seconds of intense whizzing and flashing a long deactivated metal being awoke.

Mecha Sonic, previously motionless in his green suspension tube, whirred into life. The measure of external electricity was enough to start one of his own engines.

A quick self-check ran during the boot-up. The immediate results were rather dispiriting to the robot: despite both CPUs being operational, the main engine was off; both leg thrusters were inaccessible; leg circuits weren't responding to the commands his CPU was sending. The condition he was in implied that he had been on his way to renewal when something distracted his creator, forcing him to leave the robot with only his hands and brains operating.

Yellow reinforced plastic that made his visor glistened, indicating that the grey-coated machine was now fully awake and ready to study its surroundings.

Seconds later he had a full 3D scan of the place. A two-level room; large amount of machinery inside; metal doors on each level. Sensors indicated that some of the doors were locked. He couldn't ascertain what was behind them; thick layers of steel didn't leave his sensors a single chance.

Goldish lenses dimmed for a brief moment; the robot was now experiencing a digital equivalent of confusion. There was no match for the scan in his memory banks; the place was unknown. His system clock also wasn't functioning properly, so he couldn't calculate how much time had passed since his systems had gone offline.

Mecha proceeded with studying the room. His own shape was stood in a plastic tube on the higher level; the lower level was half underwater. The place looked long abandoned: scarce emergency light panels were slowly going off, no sirens were screaming, no mad scientists were hurrying to rescue their hedgehog-shaped servants.

It did not compute.

What did compute was the fact that the water level was slowly rising. One of the doors below him was probably leaking, letting more and more liquid flow inside. It wouldn't take too long for it to reach the tube.

Leaving the place as soon as possible and finding the master after that would be a good idea.

Only there were complications. Mecha couldn't move, and he didn't even know where to move.

Rapid self-repair was out of question; the action might be compared to a human performing spine surgery on himself with bare hands and with no anesthesia. He'd have to do with what he had in his two hands at the moment; and apart from the hands themselves, it were a Tesla power coil engine and an advanced AI.

Another problem was the water. Despite being a multi-purpose robot, Mecha wasn't waterproof, and entering a wrong passage could easily result in him staying there forever, scaring fishes and rusting into a pile of mud.

A frenzied whirr came from the back of his head, where his chip was struggling to solve several problems at once.

The only possible data source present in the room, apart from Mecha Sonic himself, was a deactivated robot floating in another suspension tube. This time Mecha's memory banks were of use and offered a code name as soon as the image was analyzed.

'Metal Sonic. Has been heavily damaged during a fight against enemy zero-zero-one Sonic the Hedgehog before this unit was created. An obsolete model.'

It was improbable that the robot could provide him with valuable information about the base layout. Still, the possibility was above zero, which meant it was worth a try.

His cumbersome legs were useless in his current state. Clumsy rectangular fingers retracted to be replaced with more elegant spike-like ones. With an abrupt slurping sound two of them were ejected to hit the joints connecting his legs with his body. The metal broke; now free of the deadweight, Mecha fell on his back so his head quills sat against the green plastic. A sharp screech resounded through the room as the grey quills propelled along the back of his head like a saw chain. Moments later the hole in the plastic was wide enough for him to crawl through.

Using his hands, Mecha dragged himself across the floor towards the second tube. Its control panel was fastened to the wall low enough so he had no problems reaching it from the floor. Segmented rectangular fingers returned and tapped the keys tentatively. Several sheaves of sparks emerged from the side of the panel as it turned on; apart from that, it seemed to be still fully functioning.

Like its twin, the tube had a greenish hexagonal slab on top and at the bottom; apparently, the robot stayed in the air thanks to them. Following Mecha's commands, the upper slab retracted into the ceiling, and a set of four manipulators took its place. One of them opened a tiny lid at the base of the sleek head and then plugged a cable into a revealed jack. This was supposed to let Mecha study Metal's memory without alerting his operating system.

'Search all external memory devices for files created after 19-10-1994.'

'Access denied.'

'Repeat action: search all external memory devices for files created after 19-10-1994.'

'Access denied.'

Mecha Sonic held several output lines, none of them repeatable in polite networks. Even unconscious, the obsolete copy managed to fight him! Memory assured him that no content protection systems had been in use back then; still, there was a possibility that master Robotnik had used the old rubbish to test a new system before putting it in use… which was going to make achieving his goal slightly more difficult.

It looked as if he had to actually start Metal's operating system for some serious robot talk.

He didn't feel like taking risks. A manipulator plugged another cable into the blue head, other two undid a small protective panel below it and broke circuits that connected the internal power supplies with the rest of Metal's hardware. If the robot decided to try and do something illogical such as attack his counterpart, he would drop dead as soon as the cables unplugged and the energy supply got cut short.

A gentle hum came from the blue frame; moments later, its red eyes flickered on. Still suspended in the air, the robot spun around himself slowly, inspecting the area. Soon enough, his gaze fell upon the broken tube, then on Mecha Sonic next to the control panel.

It wasn't clear how much he understood until he broke the silence.

"ID: 000159. Code name: Mecha Sonic," he spoke in a monotone. "Latest activity: projects The rise of Death Egg, Eggrobo Advance. The rise of Death Egg project status: failed. Eggrobo Advance project status: failed; Mecha Sonic suffered significant damage. Mecha Sonic reparation status: reparation aborted 03-12-1994. Current location: the Final Egg base at the Mystic Ruins. Purpose: an object of historical importance."

It was a surprise, pleasing and unnerving at the same time. The remark suggested that the unit most likely had the information Mecha needed; and if the information was correct, it meant that master Robotnik valued the obsolete robo-Sonic enough to furnish him with up-to-date data instead of Mecha Sonic.

And it did not compute, either.

"This unit has no such information on its current status," Mecha buzzed. "Last available data: project Eggrobo Advance. Project status: in progress. This unit's last mission: obliterate enemy zero-zero-four Knuckles the echidna. Mission status: failed."

Metal's synthesized voice was unmistakably smug now. "Old as the Eggpod design. This unit's last available data: project EggmanLand. Project status: in progress; proceeding with building the first defense line in the Mystic Ruins. Relative projects: project Chaos, started: 19-11-1998."

It was like a kick in the main CPU. More than four years of inactivity! His failure at killing the echidna had probably turned out to be the last straw for master Robotnik, making offering a second chance to an even more ancient robo-Sonic an option more preferable to him than repairing Mecha. One could hardly imagine a realization more humiliating for a robot.

Still, there was that one tiny problem with Metal's version of the story.

The blue robot's red eyes were fixed on Mecha Sonic, daring him to come up with a cocky response – which Mecha gladly offered. "In this case, Metal Sonic sure possesses detailed information on how project Chaos is related to the water down below these units."

Metal's speakers produced a barely audible angry beep. "Negative. The Final Egg is not an underwater base, and presence of a large body of water inside means it was presumably hit by a flood. Additional hypothesis: the flood was caused by a natural phenomenon, such as an unpredicted seismic activity."

"Inquiry: does it mean that Metal Sonic's information is also outdated?"

His counterpart didn't bother responding to that question, and after a short period of time Mecha tried another one: "This unit's system time is incorrect. Required information: current date."

No reaction followed, again.

Mecha checked the water level; one point three five meters below the second story's floor. The floor in question was partially made of perforated steel, offering enough holes for the liquid to flow through. If he wanted to take hold of the files related to the base layout, he should better get a move on with it.

"Inquiry: does Metal Sonic possess a 3D blueprint of the base?"

The blue form didn't shift, but Mecha's sensors picked up on an increase in its chip activity. "Assumption: Mecha Sonic is willing to abandon the base."

"Repeat inquiry: does Metal Sonic possess the blueprint?"

"Affirmative."

"This unit requires a copy of it."

"Negative."

Mecha stayed idle for a moment, processing the response he had got. "Inquiry: why?"

"This unit will not share the files. But this unit will gladly guide Mecha Sonic through the base if Mecha Sonic restores this unit to original state."

It wasn't what the grey robot had in RAM. "This unit does not need a guide, but a copy of—"

"Repeat: this unit will not share the files. Addition: Mecha Sonic's reparation was aborted before the main engine was restored. Analysis of the base layout shows that Mecha Sonic, unlike this unit, would be unable to reach higher levels of the Final Egg. Conclusion: good luck trying to leave the base on two hands."

Had Mecha had teeth, he would have gnashed them into dust by that time. Making fun of his ignorance seemed to be not enough for his older 'brother'; now he needed to scoff at Mecha's physical disability.

"It appears that master Robotnik spent a considerable amount of time repairing Metal Sonic."

It was half a question that held an accusing undertone. Metal's eyes flickered a darker shade of red at it. "Mecha Sonic was offered several occasions to obliterate the prime target. After repeated failures, doctor Robotnik considered Mecha Sonic ineffective and resorted to rebuilding and upgrading this unit instead. Analysis of these units' potential shows that the decision was highly reasonable and—"

"Metal Sonic didn't mention being related to the latest active project," Mecha interrupted the rant. "Assumption: Metal Sonic has been discarded just like this unit, and sure possesses a lot of neuro-connection elements gloating like this."

A fizz escaped Metal's speakers. His grey double was not supposed to fight back like this.

The worst part was that Mecha had a point. According to Metal's own system clock, more than a month had passed since he had been last deactivated. He had been a part of doctor Robotnik's EggmanLand project, waiting for a rematch with Sonic the hedgehog to win this time. A note related to project Chaos was the last in his records, with no details provided. As Metal's logical operation system suggested, something about it must have made his role in the proceeding irrelevant and also somehow led to the base being partially destroyed.

He couldn't evaluate what could have happened to doctor Robotnik.

Sorting things out personally would be the best solution. His counterpart's decision from not so long ago; with some subtle differences.

"Further debate about these units' status is pointless." It practically meant admitting his defeat and hurt like having a dozen viruses in his system would, but he swallowed it for now and droned on dispassionately. "Current conditions: the base is about to submerge. None of these two units can function underwater. This unit does not possess any information on this capsule being waterproof. Possibility of doctor Robotnik returning to retrieve these units is estimated as particularly low. The only rational option in these circumstances is cooperation."

Sure enough, Metal had a point. As much as Mecha hated it, he had to admit that cooperation was the only option his system could suggest, too.

Still, the offered plan needed some polishing.

"Affirmative," the grey robot buzzed on general principle and shut Metal down.

Plain obedience meant leaving himself in the blue robot's mercy, which was not an option. He had to make sure Metal depended on him just as much as he depended on Metal.

Two of the manipulators retracted, letting two cutters appear. After moments of furious screeching and sparkling, slim tricolor arms dropped to the floor. Modified circuits were restored, granting Metal control over his power sources. The green plastic slid down, and the robot fell on his knees on the slab beneath him with two cords still attached to his head. Setting the timer for an auto turn-on, Mecha crawled closer to the motionless form. He fastened his left arm around Metal's neck, clutching the remnants of the shoulder tightly; making sure to stay away from the back jet, he positioned his own defective body against the opposite shoulder.

Now, to see Metal's reaction…

Once he finished, red eyes flickered into life again. The blue robot instantly knew what his successor had done to him, and couldn't help familiar fizz of fury. He turned his head slightly to catch a glimpse of his tormentor.

"This is a precautionary measure," Mecha informed him. "This unit's sensors detect that some of the doors leading out of this room are key-coded. To exit this room and go through the base, Metal Sonic will probably need to type in entry codes. This unit will gladly assist."

Metal Sonic said nothing. His main engine came alive, wheezing heavily while straining to lift the increased weight off the floor. The cords flapped and hung loosely behind Metal as he propelled both units towards one of the doors. A lid at the base of his head slid onto its place on its own, partially restoring the blue body's integrity.

The robot halted before the doorway. His sensors meanwhile informed him that his disabled counterpart's head was currently resting on his pointy shoulderpad – or at least a part of the head that could fit onto a slim piece of metal. He was aware that such an action was a way to express affection in human society, but at the moment he was less than amused. A set of sharp quills was poking the area where his head connected to the rest of his frame, suggesting rather acutely that one wrong movement could lead to him finding himself in the same state the grey robot was stuck in, if not worse. Metal possessed full information on Mecha's weaponry.

Extra careful not to compromise his output logs with unprintable lines, he buzzed, "The open button is the green one. No password needed."

There was a passage on the other side. No water.

"This is the shooting range," Metal went on rather conversationally, implying that he hadn't been entirely kidding when offering to be a guide. "Test targets bear a resemblance to enemies zero-zero-one Sonic the hedgehog, zero-zero-three Miles 'Tails' Prower, and zero-zero-four Knuckles the echidna."

Mecha said nothing.

Clutching onto one another like a couple of drunk hobos and swaying slightly in the air, they wandered down a dark passage that soon entered a room that looked like a section of an oval shaft. Pipes twisted above them, running through one another as well the walls and the ceiling. The lane ran along the left wall; water was glittering on the right, suggesting there was a pit somewhere deep underneath. Mangled dolls were drifting slowly across the surface, as if the flood had washed some animal corpses from the nearest pet cemetery. Mecha's sensors studied the area impassively.

"Disabling this unit was an unwise decision," Metal broke the silence again. "This unit does not possess all entry codes. Some codes might have been changed since this unit's last deactivation. Each door is equipped with a battery backup unit, but some of them might be damaged by the flood. This unit would need to enter battle mode to get past those doors."

Mecha stretched his right arm forward, once again replacing his regular fingers with spike-like projectiles. "This unit will take care of them."

"Apt information. This unit has no entry code for the door that is ahead."

They entered a smaller room that indeed had an oblong metal door at the far end of it. Locating the door lock, Mecha fired a single finger at it; the projectile ricocheted off, leaving the device slowly sparkling into oblivion.

There was a strange sound behind the door. As if someone really powerful was pushing it with all their might; or probably something.

"Inquiry: how does Metal Sonic know there is no water ahead?" the grey robot buzzed demandingly, his calculations speeding up in an equivalent of quickly growing panic.

"This unit does not."

It took Mecha several long seconds to process this information; it did not compute at all. "Metal Sonic's previous statement: 'None of these two units can function underwater'. If these units enter the passage that is—"

"Affirmative. This unit said so."

The door bulged. Several of the screw-bolts that nested in the doorframe flew out with a pop, followed by jets of water.

Metal Sonic turned his head to take a better look of the yellow visor. Not in hopes to find traces of fear there – robots had always had problems with facial expressions; simply to make sure the image stayed in his memory.

"This unit lied."

The metal panel exploded into their faceplates, and a mass of water swept over them. The impact tore Mecha off Metal, and both robots flew back further into the training chamber. Grey claws scraped the metal floor, to no avail; the flow dragged Mecha back into the shaft and down into a pit. His form kept shuddering frantically, desperate to force itself out of the deadly trap. There had to be a way; his chip was overheating even with a cold substance around the spiky head, calculating with full power.

Sensors malfunctioned.

Vision went offline.

There had to be a way…

Metal Sonic watched the darker robot float downwards past him. The fire his engine had been producing went off, now replaced with a gentle jet of bubbles. He studied the stumps left of his arms; the impermeability of his body was not absolute now. Some circuits were going to rot… not the vital ones, though.

The water had already filled the shaft almost completely by that time. Struggling against the flow and using his legs to steer, he leveled himself with the room again before heading towards the now-open door.

Mecha really shouldn't have dismantled his hands. The action had left Metal with a personal grudge... as well as an upgraded version of his Maximum Overdrive attack yet to be tested underwater.

He checked his memory; all of the conversation and the records of their attempt of escape were safely there.

If still alive, doctor Robotnik would have to reconsider his opinion about that unit.

.w.

Author's note:

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