Dean had recognized that weathered, stubbly face, those weary yet old-wolf-sharp eyes—it was unmistakably his own!
It was his future self!
"How did I end up like this? What happened?"
Driven by curiosity, Dean followed the survivors all the way to a shelter converted from an underground parking garage.
The entrance had been reinforced with rusted sheet metal and sandbags. Inside was dimly lit by several flickering oil lamps, and the air reeked of sweat, mildew, and cheap alcohol.
In one corner, he saw Castiel.
The former angel was now curled up amid a pile of rags. His iconic trench coat had long since become filthy, stained with unknown blotches.
He clutched a half-empty plastic bottle tightly in his hand, filled with murky homemade liquor.
His eyes were unfocused, his face numb and despondent from the long-term ravages of alcohol and things far worse.
Dean could not sense any angelic power from him. He was like a vessel that had been completely hollowed out and discarded, little more than a useless wreck.
Dean blended in with the crowd like they were a gathering of vagrants.
Until, a day later, he witnessed something that tore his heart and soul apart.
While following the group on one of their outings, curious about what had happened to the city, he slipped into the central plaza while no one was watching. The instant he saw it, his pupils dilated in utter disbelief.
The center of the plaza had been transformed by an evil power. Huge runes burned with green flames across the ground.
A figure sat upon a towering throne built from bones and twisted metal.
It was Sam!
No, it was not Sam. Inside that familiar body lived Lucifer!
He lounged lazily against the throne, toying with a flickering ball of black flame