They would all die.
The thought comforted him as he cautiously made his way through the castle dungeons. By dawn there would be no one left. No more whispering as he left a room. No more accusations. He'd never have to see their looks of disgust, or worse, pity. He yanked the hood of the cloak further over his head just in case there was someone still roaming the castle at this time of night. The soft sound of footsteps made him pause and duck into an alcove, eyes narrowed at the approaching light. A glowing sphere of light floated a just few feet away, bobbing gently in the air.
"I know you're there."
Snape's voice made him panic momentarily. This was exactly what he'd wanted to avoid! For some time there had been rumors that Severus' loyalty was in question… some, namely Bellatrix, weren't certain that he was still loyal to the cause. After all… one can only be a double agent for so long before he either switches allegiances or gets killed by the opposition. He held his breath, hoping that the potions master would simply leave before latter became a reality.
"Don't think for one minute that you have managed to fool me. I always knew you were-" Snape suddenly hissed in pain. "However, that is of little consequence at the moment, our guests have almost arrived. I will ensure no one gets past this point."
He crept silently into the hallway, not even sparing a glance toward the professor. It didn't take long to reach his destination; a portrait of the Garden of Eden that hung in a long forgotten room deep in the bowels of the dungeons. He lifted a hand to caress the emerald serpent sunning itself on a rock, which then lifted its head from the canvas and bit his palm. He winced at the sting and laid his now bleeding hand on the stone wall beside the frame. In one breath-taking moment he felt Hogwarts rush to answer his unspoken request, her power pulsing against his palm. Where the portrait had been, a large black iron door appeared and slowly swung open to reveal row upon row of Death Eaters. The ranks parted for an applauding Voldemort to enter Hogwarts. "Brilliant. Absolutely brilliant. But one could hardly expect less from you. 'Once a Slytherin, always a Slytherin.' Any special requests my Lord Slytherin?"
Emerald green eyes glittered in amusement as the man once known as Harry Potter lowered his hood. "Kill them Tom... kill them all."
It would be remembered as the bloodiest night in Wizarding history; one of fire, blood, and screams. When the sun rose the next day, Harry Potter had died, and Salazar Slytherin had been reborn.