A/N: All I really have to add here is: And here we go...

Silence was not preferable to the sound of Tails screaming that Sonic had hoped to hear.

On the top floor of the skyscraper, sunrise lit up the eastern windows and illuminated the wrecked room. It looked like a ghost town out of a horror movie. White, box-shaped computer monitors sat on desks or lay on floors, half with screens crushed. Desks sat on their side so they towered precariously above Sonic's head. But other than his and Knuckles's footsteps, he heard nothing

At least if Tails was screaming, Sonic would know he was near. Know he was alive.

Silently, without even needing to glance at one another for direction, Sonic and Knuckles headed for the stairwell behind a door hanging on one hinge. Sonic wanted to sprint through the place, tear it down if he had to. But Knuckles tested the first step and it creaked. Ever. So. Slightly.

Sonic held his breath, and they both held completely still for what felt like an hour but was probably only a minute. But they still heard nothing. Maybe the murderer wasn't even here. Maybe this was a false lead.

No, Sonic thought resolutely. Not because it wasn't. Because it couldn't be.

So they carefully descended the stairs, each movement careful and deliberate. When Knuckles stopped at the first door one floor down, Sonic shook his head and continued on. Until Sonic heard Tails's voice or could go no further, he wasn't going to waste time searching every floor.

Three floors down, they hit water. It filled the stairwell, thick and dark, allowing no guess of its depth, just like the water outside. Sonic swallowed hard, but there was no moisture on his tongue and he nearly choked. He spun around, looked at Knuckles who stood right behind him, and pointed at the last possible door before the building succumbed to the flood.

And then Tails screamed.

Sonic bolted, no longer caring about how much noise he made, no longer caring if he left Knuckles in the dust. Tails wasn't dead. Tails wasn't dead.

But he might be dying.

Sonic slammed through the door from the stairwell. The door snapped from its rusted hinges and went flying several feet before clattering to the ground. The sound deafened Sonic, and he winced when it struck his eardrums. And then, a second later: "SONIC!"

"I'm here!" Sonic screamed back. Let the serial killer hear him. Let him know who was coming.

"SONIC! RUN!"

He froze, if only in shock. Run…? But…it sounded like Tails wanted him to…run away…

No. He couldn't keep running away. He ran from Amy, and then from her corpse. He ran away from his friends again and again and again. And he wanted to run away. But not because he was scared of some murderer.

Instead, Sonic forced himself onward. The floor looked like the one above it, with desks and computers carelessly discarded across what had once been an office. But the computers…some of them were torn to pieces, like they'd been scrapped for parts.

The hair on the back of Sonic's neck stood up, alerting him to someone breathing on his skin, and he spun around. But it was only Knuckles, who clamped a hand over Sonic's mouth to stop him from screaming.

And then Tails whimpered.

Sonic's heart was a glass figurine struck by a mallet and crushed to the dust at that sound. He scrambled on, tripping over cords left in the aisles—or had once been aisles—as he went, barely remaining upright.

He swung through a turn, sliding almost to the ground. He caught himself with his hand, and the glass on the ground sliced open his glove.

As he shoved himself upright, his eyes caught sight of a flash of yellow. "Tails!" he shouted.

Tails opened his eyes from where he crouched in the corner. His hand clutched at his opposite arm, which hung unnaturally still at his side. Red dyed the palm of his glove where it wrapped around his arm. Even from this distance, Sonic saw Tails's bloodshot eyes. "Sonic," his little brother said, his voice breaking, "get out of here."

"I'm not leaving you," Sonic said. He took a quick step forward.

"Incorrect move, hedgehog."

He should have darted forward. But instead he froze, as did Knuckles behind him. They knew that voice.

It normally belonged to Sonic.

Sonic pressed his hand to his throat, as if that would reveal whether the words actually came straight from his mouth. But after that brief second of self-doubt, he recognized the undertones of metal and robotics attempting to make noises only living things could.

And Metal Sonic came into view.

Though he now stole Sonic's voice, he barely resembled Sonic's memory of himself or of the original Metal. Portions of blue paint on its body had been worn away to reveal the silver underneath. Its joints were exposed and its eyes illuminated bright red. Congealed blood smeared its every surface, probably long since forgotten.

Except for the bright red dripping from his fingers, blood that once belonged to Tails.

Sonic's thoughts halted. Instinctively, his feet itched to continue forward, his fingers ached to clutch Metal's head and crush it into scrap against the floor. But he…couldn't…think.

How could it be Metal? Sonic had destroyed him back at Stardust Speedway right before he rescued Amy for the very first time. Had Eggman remade him? It wouldn't be the first idea he'd recycled. But Eggman wasn't a killer, was he?

"Why?" Sonic said finally and his voice cracked.

"Only one can remain," Metal replied evenly. The robotic inflection sounded so wrong in Sonic's voice.

Sonic choked. Metal had said that once before while racing down the Speedway, right before he exploded at the end of their race. It seemed he'd changed his mind on which one would remain.

"Did you do all this to bring me here?" he demanded, swinging out his arms. What he meant to demonstrate, he didn't know. All this? All those lives lost…Tails injured…

Amy's explosive life wiped from the earth at the age of twelve…

"I'm not like this!" Sonic cried. "You're built using my lifeform data, right? You shouldn't be like this either! Is Eggman making you do this?"

Metal tilted his head to one side, and Sonic realized it was meant to be a smirk. "I stand alone. And I know you. I am not you; you are me."

"Why would you hurt them?" Sonic screamed.

He needed to know. He should be jumping into action, no questions asked, but he needed to know. He could not go on without knowing.

Was this same darkness in him?

"So we can begin," Metal replied. His eyes glowed brighter as his head lowered.

And then he exploded forward.