Disclaimer: I don't own 'Supernatural' or 'Merlin'; they belong to their respective creators, and I'm just borrowing them for this story

Feedback: Always a pleasure

AN: Hope this chapter works; it was surprisingly tricky to get it right, and I had to cut a couple of other monster hunts out of future chapters when I realised that they didn't quite work after these events- plans to incorporate them just didn't work-, but I do have something interesting planned for the future…

The Cup of Life

Since coming to Camelot, Merlin had seen and done a lot of things that he couldn't quite believe in- just talking with Kilgharrah was certainly at the top of that list, but it was far from the only item present-, but his current situation was definitely one of the strangest; he was actually working with a warrior of the Creator...

He had encountered several strange creatures in his time, but this was something else; he couldn't remember the last time that he'd encountered a creature that was apparently meant to be this... good. Even dragons could be of questionable allegiance, but everything that Gaius had told him about the Celestials made it clear that they were primarily dedicated to battling a type of evil that he had never encountered and never wanted to face, and yet they were there to wage a war against the most twisted of all creatures.

Demons...

Merlin had encountered a few ghosts and spirits in his time, and he'd faced his share of evil magic-users even before Morgana turned against Camelot, but the idea of there being sentient creatures out there that would destroy Camelot just because they wanted to destroy things was... well, 'terrifying' was the best word that he could come up with.

Still, for the moment, he didn't have to worry about the; all he had to do was sneak Castiel into Camelot and get him to the main throne room so that he could negate the spell that Morgana had cast (Dean had asked why 'Cas'- Merlin couldn't believe that anyone would give such a name to a Celestial, but Castiel didn't object to it so Merlin didn't see any point bringing it up- couldn't just take them there immediately, but Castiel had explained that something about recent events prevented him doing that, and the de Chesters had apparently accepted that). Sam and Dean were assisting some of the knights in making a few patrols of the city, just in case any other creatures showed up before they had negated Morgana's spell, which left Merlin and Castiel with the task of getting to the throne room to deal with the long-term problem while everyone else was otherwise occupied.

It was a disturbing and unique situation, but it was still one of the most engaging experiences he'd had since he found himself charge with Arthur's protection all those years ago, and the current experience would give him time to ask one of the more pressing questions facing him since the de Chesters and Castiel had revealed their real reasons for coming to Camelot.

"So... what is the... problem... you need my help with?" Merlin asked, looking curiously at the celestial- or his vessel, anyway; Merlin understood why the being before him was using such a form, but he still had to wonder what Castiel would look like in his natural state- after they had spent some time walking through the corridors in silence.

"An enemy of ours has acquired the Cup of Life, and intends to use it for the same purpose that Mergana and Morgause used it for in their attack on Camelot," Castiel explained, Merlin pausing for a moment to take a detour down a rarely-used side corridor even as he continued to listen to Castiel's explanation. "I am aware of a ritual that will allow us to destroy the Cup once and for all so that it may not be used in this manner again, but it requires your assistance, due to the bond you forged with the Cup when you used it to save Arthur and your mother."

"Oh," Merlin said, looking at Castiel for a moment, briefly stuck for a more appropriate response to the news that he had just received- the idea that anyone could do what Morgana and Morgause had done to create the immortal army again sickened him on its own, even without the shock factor of the other information Castiel had revealed- before he asked another question. "There's... really something you can't do? I mean, from what Gaius told me about you… well…"

"We are the Creator's warriors, Merlin, but there are still things that even a… Celestial… cannot do," Castiel explained, nodding in confirmation at Merlin, with no sign that he resented Merlin bringing up something as personal as a potential weakness. "We must all have limitations to ensure that we do not forget the purpose for which we were created, and are provided with the opportunity to find our own paths as we seek to fulfil our Father's will."

"Your... father?" Merlin asked, puzzled at the term.

"The Creator," Castiel explained, a slight smile on his face as he spoke. "Few of us have seen him, but he is father to us all; we were his first creations, until he entrusted us with your protection after he had created Man."

"Oh," Merlin said, out of a lack of anything else he could say to such a statement until another thought occurred to him; he'd never felt comfortable asking Kilgharrah this kind of question- particularly not after the near-destruction of Camelot caused when the dragon had attacked the kingdom after Merlin freed him, given the circumstances of how that attack was halted-, but something about Castiel prompted him to ask it anyway. "Did you ever... resent it?"

"Resent what?" Castiel asked, looking curiously at Merlin.

"Being ordered to protect us," Merlin clarified. "I mean, when I first learned that it was my destiny to protect Arthur, I wasn't that interested in it- thought he was nothing but an arrogant prat-, and for the first few months I was mostly doing it because protecting him meant protecting everyone else in Camelot…"

"And you are wondered if we ever felt the same about humanity?" Castiel asked.

"Well… you were here first, weren't you?" Merlin asked, feeling increasingly awkward even as his mouth continued to speak. "Wasn't being told to look after us a bit… well, demeaning?"

For a few moments, the two walked in silence, only part of this new lack of conversation caused by a close encounter with a couple of knights on patrol, but just as Merlin was starting to regret asking the question in the first place, he received an answer.

"Some of us did resent it at first," Castiel replied, his expression even more solemn and unreadable than it had been earlier. "Lucifer, one of the first angels and regarded as the most beautiful of us all, rejected our Father's demand because he felt that you were unworthy of the love that he had shown you, convinced that you were not the wonders that Father believed you were… but even if some of my brothers agreed with that assessment…"

"You didn't?" Merlin asked.

"Even before I was assigned Dean and Sam as my charges, I appreciated the wonder of your people as my father's greatest creations, capable of far more than what Lucifer was willing to allow himself to see," Castiel said, smiling as he looked at Merlin. "You are flawed, yes, but you are willing to forgive the flaws of others and see them as they could be, rather than defining them by past mistakes."

"And… Celestials don't?" Merlin asked.

"Lucifer and Michael have been separated for millennia and they still long to destroy each other for their respective role in our Father's plan," Castiel said, a grim expression on his face as he revealed that information. "I trust that is a sufficient example for you?"

"Oh," Merlin said, the expression on Castiel's face prompting him to remain quiet as they continued to walk through the corridors of Camelot.

He might know little about the Celestials, but Merlin knew enough about people to know when they weren't interested in taking a topic any further, and Castiel's current manner made it clear that he had reached that point.

As they came to the door of the throne room after a few more minutes of silent walking, they halted at the sight of a guard standing in front of the main doors, before Merlin raised his hand and made something fall over down the corridor at the other side of the door. As the guard walked off to investigate the sound, the warlock led the Celestial up to the door of the throne-room, where he quickly opened it with another spell and slipped inside, Castiel following him in before he had closed the door behind them.

"We're here," he said, smiling as he looked back at the celestial.

"Good," Castiel said, taking in the room with a thoughtful glance before he looked curiously back at Merlin. "Can you recall where Morgana Pendragon was when she let out the scream?"

"It was..." Merlin said, pausing for a moment as he closed his eyes to concentrate on the memory- a lot had happened on that dark day, but he'd never forget the sight of Morgana looking at him and Gaius in anguished betrayal once again- before he opened them and pointed at the right spot.

"Here?" Castiel said, walking over to stand a short distance from the position that Merlin had just indicated, holding out his hands as though he was trying to 'feel' the location where Morgana had been.

"Yeah, that's it," Merlin asked, looking at the other man with a sudden sense of anxiety at what they were about to attempt. "Just... hurry up, could you? We can't wait around for long; this isn't exactly the kind of place that nobody comes to, you know..."

"This will not take long," Castiel said, looking solemnly at the young warlock. "We are both prepared, and the spell is simple to cast; all that we must do now is channel our energy, and it shall be negated.

"And... and this will stop it?" Merlin asked, trying not to show his enthusiasm at the thought of casting a spell with a Celestial; he was a figure of legend, he wouldn't start… whooping like he was an enthusiastic child! "It'll... un-ring the dinner bell?"

"That is correct," Castiel confirmed, holding out his hand as he stared at the location that Merlin had indicated. "Just concentrate with me, and we shall be finished soon."

With nothing else to say to that statement, Merlin moved in to position next to Castiel, their gaze focused on the area where Morgana had let out that terrible scream so long ago as he held out his hand.

As he stood alongside the Celestial, one hand out in front of him, Merlin suddenly felt a near-overwhelming sensation of something pulling him towards the other man, his very energy and magic emerging from his hand to merge with the holy power of the Celestial, their combined power being subsequently channelled through the disruption caused by Morgana's spell- a disruption that he'd never been aware of before but could now suddenly see as though it were a solid, tangible thing-, soothing and calming the damage to the world that Morgana had created, turning Camelot itself into a place of danger when it should be a safe place for all who lived there…

Finally, after a few moments had passed, the distortion seemed to fade from Merlin's senses, and he lowered his hand to look at Castiel.

"Did…" he began, before he fell back to the ground, suddenly feeling as though he'd just been forced to participate in a particularly brutal training session.

"The spell took a great deal out of you," Castiel said, looking apologetically at Merlin as he crouched down beside him before holding out a hand to place it on the young warlock's shoulder. For a moment, the two men looked at each other, Castiel with an intense stare on his face while Merlin looked weakly back at him, before Castiel removed his hand from Merlin's shoulder with a puzzled expression on his face.

"Odd," he said, looking between his hand and Merlin in confusion.

"What?" Merlin asked, looking at the Celestial, uncertain what his strange new friend had expected to happen. "What just-?"

"We have to go," Castiel said, standing up and helping Merlin to his feet, evidently resolved to ignore Merlin's question. "I shall explain later."

Stuck for anything else to do, and with his legs still slightly shaky underneath him, Merlin simply hurried along as Castiel led him towards the door, the two only briefly pausing to allow Merlin to distract the guard with another spell before they slipped through the door and began to hurry down the corridor.

On some level, Merlin knew that he should be asking Castiel what he had actually been trying to do earlier, but the rest of him just wanted to rest and get his strength back after that spell he'd just cast; he'd worry about that when he had more time…