A/N: The final trial of the Angel Tablet. Set somewhere in Season 9, since Season 8 will probably be busy with the Demon Tablet. In my mind, Cas finally comes around and brings the tablet to Kevin.

Can be Destiel if you want to see it that way. I wrote it with something more platonic and fraternal in mind.

This is my first fanfic in over two years. I'm probably rusty, so bear with me.

"I've translated the final trial," Kevin said nervously.

"And?" Dean prompted.

"And you're not gonna like it." The young prophet looked at the group before him. Sam and Dean waited expectantly, but Cas looked as though he might know what was coming. Kevin took a deep breath. "You have to sacrifice a willing angel with his own sword, on a holy altar."

Dean stared at him. "What?"

"That's… what it says. I've reread it fifteen times, but the translation's still the same."

"There has to be…" Dean began, but ended simply with a forceful, "No."

"Dean…" Cas said quietly with a resigned look.

Dean turned to him. "No! We're not doing that. I don't care what the stupid tablet says. We'll find another way."

"There is no other way!" Cas shouted back with a ferocity that reminded them that he was, even still, a warrior of God.

"I am not going to kill you!"

Castiel narrowed his eyes. "Then all of this-" he gestured at the tablet, "-has been for nothing." He turned away and vanished with the sound of fluttering wings.

"I know you don't want to hear it," Sam finally spoke up, "but he may be right."

"Shut up, Sam."

Castiel entered the nave of the church, silently walking up the aisle. Narrow panels of stained glass rose up on either side. Above the altar, the setting sun came through the rose window, throwing patches of red, blue, and green across the floor.

He looked around and nodded slightly, allowing himself a melancholy smile.

Dean vehemently rearranged the contents of his desk, for no other reason than it was there, and it was something to do. Something to keep his mind occupied. He had succeeded to the point that he didn't hear the flurry of feathers outside his doorway, until he became aware that was not alone.

"Are you ready to finish what you started?" Cas asked, leaning with one hand on the door frame.

"I doubt I'll ever be," Dean replied, tossing a pen down on the desk.

"We don't have a lot of time," Cas said, rocking slightly as though deciding whether to enter the room. "Heaven will be trying to stop you from closing the gates."

"I know," Dean said, sitting down on the bed and dropping his gaze to the floor. "But we still have to find a holy altar."

"I've found one."

Dean looked up. "You have?"

Cas nodded. "There's a church, not far from here. It's… it's nice." He looked away. "Most people don't get to choose where they die."

"You really want to do this?"

"Want, no. But I need to do this. So much of what's wrong in Heaven is my fault. And really," he cocked his head and almost smiled, "where are you going to find another angel so willing to die for you?"

They set out for the church just before midnight, when it would likely be empty. Sam insisted on coming along, giving his reason with a shrug. "Moral support?" He leaned awkwardly against the front pew as Cas held out his angel blade to Dean.

Dean reluctantly took it as Cas sat on the edge of the altar. The angel loosened his tie and took it off, holding it for a moment before shoving it into the pocket of his trench coat.

"I don't know if I can do this, man," Dean muttered, looking at the blade in his hand.

"You have to," Cas replied. "It's the only way to end this." He looked around the room for a moment. "If it makes it easier, remember when I betrayed you. Remember all the times I let you down." He gave Dean a pleading look.

Dean shook his head. "No, if I'm going to remember anything, it's that you were always family." He could feel tears trying to escape as he looked the angel in the eye. "I love you, Cas," he said as he thrust the blade into his heart.

Castiel's eyes widened as he gasped in one last breath of air, and as he began to slump backwards, Dean gently lowered him onto the altar, resting his own head on the angel's shoulder. Through closed eyelids, he could still see the bright light emanating from Cas, and feel something burn into his hands where they remained holding onto the angel.

Dean didn't move for a moment-couldn't move-until Sam came up behind him and placed a hand on his shoulder.

"Dean… come on," he said softly.

Dean slumped to his knees on the floor, and stared at the feathery pattern etched into his skin. He was half aware of his brother's phone ringing.

"Yeah?" Sam answered. "Kevin? Yeah, it's done." There was a pause. "Wait, what?"

Back on his safe-house-boat, Kevin held the tablet in his hand. "There's a sort of footnote," he said into the phone. "I didn't see it before. It's like Metatron added it as an afterthought. It says, um… something about the martyr's salvation. 'Cast aside the sword and anoint the fallen with holy water.'"

"Does that mean…" Sam began.

"Uh… maybe?" Kevin replied. "At this point, I don't think it could do any harm."

"Right. Thanks, Kevin," Sam said, hanging up. Dean had not moved from his place on the floor. Sam walked past him and pulled the blade from Castiel's chest. Tossing it to the floor, he headed back towards the church doors.

Dean looked up as the sword clattered across the wood floor. "What are you doing?"

"I guess we'll find out," Sam replied, splashing a hand in the holy water font. As he returned to the altar, Dean stood, giving him a bewildered look. Sam hastily drew a cross on Cas' forehead with the water, and muttered some Latin that seemed to suit the occasion.

For a long moment, nothing happened. But then, gradually, the wound visible through the hole in Cas' shirt faded. And much more suddenly, his eyes shot open as he took in a breath of air. He looked around, taking in Dean's expression of shock, and Sam's huge grin.

"Cas?" Dean said finally, his expression shifting into hopeful.

"Yeah," Cas replied, though he did not seem sure of the answer.

"You're alive."

Cas made a cursory examination of himself. "It would appear so." Dean offered him a hand and pulled him back upright and into a hug.

"How do you feel?" Sam asked.

Cas looked at him over Dean's shoulder. "Um… small."

Dean pulled away and looked at him. "So, what does that mean? Are you…"

"Human?" Cas asked. He looked thoughtful for a moment. "Yes, I think so. No powers, no angel radio… Just… me." He looked from one brother to the other. "How did this…?"

"Kevin," Sam replied. "He found a thing." He waved his hand dismissively. "I'll explain later."

"So what are you gonna do, now you're a mere mortal?" Dean asked.

Cas' eyes widened as he took a deep breath. "Honestly? I'm starving."