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"Sephiroth!" Zack's voice echoed along the passageway as he ran after the other SOLDIER. Cloud stumbled to a halt a few paces from the lab door and slumped to the ground. Everything was going wrong; his hero changed almost beyond all recognition. Sephiroth had been acting strangely ever since his arrival in Nibelheim, but it had only gotten worse since that secretive trip into the Mount Nibel reactor. Since he found the secret passage to the corridors beneath the Shinra mansion. Since he found the library and the lab. Until finally today something changed; something alien had looked out through Sephiroth's green eyes. "Cloud!" The radio on his belt crackled with Zack's voice. "Cloud, get up here. The town's on fire! Sephiroth-" A burst of static and the radio went silent.
"Zack?" Cloud clicked the radio. No response. "Dammit." He pushed himself to his feel, scowling as he did so. What could he even do now? What good would he be to Mom or Tifa against someone like Sephiroth, the pinnacle of the SOLDIER program? Nothing fazed Sephiroth; that dragon they encountered on the way here fell to one sword-blow. No. He had to do something. Anything. Mom was mom. And Tifa he had promised to help. He thumped his fist against the wooden door set into the wall.
"Such commotion." Cloud froze at the smooth voice. They had all tried and failed to open the locked door in the weeks Sephiroth spent down here. But somehow there was someone in there. "Who raps upon the door of my tomb this night?"
Cloud blinked and backed away from the door. "Who's there?"
"I believe I asked your name first; common courtesy is to introduce yourself first, no?" The voice paused. "Is time too pressing?" An urgency entered the voice's tone. "Was I dreaming or did I hear his name called in my presence?"
"You mean Sephiroth?" The air chilled in the ensuing silence.
"Yes," the voice hissed.
"You did. He's here, he's attacking the town."
"Lucrecia's child yet lives." Silence. No, not quite. Something was moving in that room. Wood scraped against wood and footsteps echoed on stone. "He must now know the truth of his creation." The voice was getting angrier. "He is too much like his father."
"What-" The radio interrupted him with a fresh crackle of static.
"Cloud, you need to get out here now." Zack sounded panicked. "Sephiroth is heading for reactor. He's- She's-" He made a strangled noise. "Cloud, Tifa's gone after him. I'm-" The radio crackled and fell silent.
Cloud's heart hammered in his chest. "I need to help Tifa." He managed two steps before the voice sounded louder than ever.
"A friend? How noble." The voice chuckled.
"I made a promise and I need to keep it." Cloud ran for the stairs. Another two steps and something clicked behind him. He stopped, unable to move. The door creaked and despite every desire to keep on moving, every certainty that he should resist, Cloud glanced over his shoulder. The door swung open, surges of flowing ragged red fabric curling around the door-frame. Glinting metal, black leather, black hair. And in the centre of the mass was a pale figure; paler than any man Cloud had ever seen.
"I have atoned for my crimes long enough." The man's eyes narrowed. "Now my sleep is interrupted, I dare not allow another crime to be committed as a result of my own." He stalked forward; all Cloud could do was stare. "My name is Vincent Valentine. I will aid you."
Cloud did not even enough time to take in the full horror of the flame-wreathed town before Vincent grabbed his uniform with what looked like a metal claw. An agonised glimpse of his house on fire. Mom- The next thing he knew he was hurtling through the air. Cloud tried to look back through the rippling folds of Vincent's cloak; already the town was too distant. She would be okay. She had to be. Mom might even not have been home.
The ground rushed up to meet the pair of them, Vincent barely reacting as he smashed into the ground on both feet. With a heave they jumped up again, Vincent's leaps covering, vast, absurd distances. Each impact rattled Cloud's teeth, but he said nothing. Was that Zack glimpsed between one jump and the next? No time. They reached the reactor in a matter of moments. No sign of Sephiroth or Tifa. Was she already inside? Cloud dashed for the door, Vincent on his heels.
The scream of anguish sent Cloud skidding to a halt for a moment and then he ran with all his might. Tifa. His heart lurched at the sight of her slumped form below him. She was crying. Relief followed by a sinking feeling in his stomach. Tifa was kneeling above the prostrate form of her father, the Masamune jutting out from the floor beside him. A moment later she muttered to herself as she staggered to her feet. "Your friend desires vengeance," Vincent said.
"We need to stop her." How could he get down to her? The walkway that should be there was missing-
"I leave that to you. I am needed ahead." He grabbed Cloud's uniform again and the reactor blurred as they darted forward. Tifa whirled in surprise, the Masamune clutched in her hands.
"Shinra," she spat. "You-" Cloud tore his helmet off. Tifa's expression softened. "Cloud?"
"Tifa." He took a deep breath as her arms trembled. "Don't do it."
"Revenge does not suit one such as you," Vincent remarked as he strode past her. "Save yourself while you still can." He paused and turned back to her. "This one made a promise to you. Take this moment to mourn your loved ones and then leave this place." He glanced at Cloud. "Leave Hojo's spawn to me." Vincent muttered the last few words through clenched teeth as his skin darkened. His body grew bulkier, his hands clasping in on themselves as his nails extended. "I thank you for this opportunity."
Vincent vanished into the next chamber as Tifa let the sword drop to the floor. "You- You came for me," she murmured.
"Sorry I was late," Cloud replied scratching his head.
Tifa shook her head. Somewhere ahead what sounded like an animal attack preceded a panicked shout as a struggle began. Glass shattered and the fight grew louder. Tifa slumped down beside her father's body; Cloud reached out to touch her shoulder. Tifa grabbed his hand and clung to him as she sobbed. He embraced her, stroking her hair as she mourned. When Zack arrived all he did was nod to Cloud before rushing past and into the maelstrom of conflict beyond.