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: For 'Supernatural', this is set in Season Six, shortly after 'Unforgiven'; Sam's soul has been restored and the Winchesters think that Crowley is dead, and are presently unaware of Castiel's secret agenda. For 'Merlin' this takes place between Seasons Three and Four (Probably closer to Three than Four), with Arthur currently regent while Uther is in a near-catatonic state after his daughter's betrayal, and Morgana and Morgause are missing

The Cup of Life

"All I'm saying, Sammy, is that at least we got a simple one," Dean said, as they slung the last of their equipment into the boot of the Impala.

"What does it say about our lives when a werewolf is 'simple'?" Sam countered, looking over at Dean with a pointed stare.

"Well, it was," Dean replied, smiling at his brother. "The guy deliberately changed in places where he'd go after people he had a grudge against and didn't show any signs of wantin' to stop; one of the most clear-cut cases we've ever had."

"Yeah, I know..." Sam said, shaking his head wistfully at the thought as he sat down in the passenger seat of the Impala, staring out at the road in front of him as Dean sat down in the driver's seat.

Hunting had never exactly been easy, but it seemed like it had only become slightly easier since he'd returned from the Cage and they'd averted the Apocalypse; the Arachne and dragons had been more challenging than the conventional monsters they'd faced, but at the same time they were still just monsters at heart...

He just wished that dealing with everything else that had come up during the crisis could have been solved as easily. With Adam still stuck in the Cage after they'd exhausted whatever favours they could pull with whatever higher powers were able to help them, Dean's collapsing relationship with Lisa, and everyone he'd let down during that hunt when he was soulless, Sam was starting to feel like hunting had lost whatever 'black and white' it had possessed.

He'd known that things in the hunting game weren't as simple as Gordon had claimed they were back when they'd first met him- Lenore might have proven him right, but she'd hardly been the only evidence needed; what about those ghosts who were acting to avenge secret crimes or protect abuse victims, even if some of them still went about it the wrong way?-, but after the year he'd had, he'd just like to tackle a few hunts where there was a clear-cut way of doing the right thing that would exclusively focus on them saving people rather than having to sacrifice some people or failing to save others in order to stop the big threat.

The werewolf thing had been a good example of what he wanted to accomplish, but they'd still arrived too late to save the werewolf's earlier victims, even if he'd clearly been a monster; was it asking too much to have one crisis where they could just stop the bad guy and save innocent people?

"Hello."

"Whoa!" Dean yelled, slamming on the brakes as he turned around to look at the back of the Impala, taking in the sight of the Winchesters' familiar angelic ally sitting casually in the back seat as though he'd been there since they started driving.

"Damnit, Cas, would it kill you to call rather than pop in like that?" Dean said, glaring in frustration at his friend.

"Things are reaching a crisis point," Castiel said. "I did not have time to find my phone, and your help is needed if we are going to avert this latest potential problem."

"Really?" Sam said, turning around to look at their friend as Dean parked the car on the side of the road; the angel might be frustrating at times, but if he thought that something was urgent, it was probably important. "What's up, Cas?"

"A demon has acquired the Cup of Life," Castiel replied, looking solemnly between the two brothers.

"The what?" Sam asked, looking at the angel in confusion.

"I believe you would know it better as the Holy Grail," Castiel clarified.

"Oh, thanks- the Holy what?" Dean said, looking at the angel with new interest.

"The Holy Grail," Castiel repeated, looking at Dean with that quizzical expression the angel always assumed when he wasn't entirely sure if he'd made a social gaffe of some kind.

"No, hold on, the Holy Grail?" Dean said, still looking like he was having trouble processing what he'd just heard. "The cup Jesus drank from at the last supper, the focus of the greatest quest of King Arthur and his Knights of the Round Table, Indiana Jones and the Last Crusade, all that?"

"I am not at liberty to divulge the origins of the Cup of Life," Castiel said, looking over at the older Winchester in a firm manner that put them in mind of the way he'd refused to answer questions back when the brothers had first met him.

"Jesus a complicated topic or something?" Dean asked, trying to sound more casual about it than he felt; even after everything else they'd dealt with since they'd learned that angels existed, Jesus was one area that they had yet to really ask many questions about.

"Or something," Castiel said, nodding briefly at Dean before he continued speaking, his tone making it clear that he wasn't going to indulge their curiosity on that front. "What is important right now is that the Cup has fallen into demonic hands, and they are using it to create an army of undead warriors-"

"Hold on; undead?" Sam repeated. "I thought the Grail was a holy artefact-"

"As I said, the Cup's origins are... complicated," Castiel said. "When a drop of blood is added to the Cup, and a specific ritual is performed, the Cup has the power to transform the subject of the blood that was added to it into an immortal, undead warrior, loyal to the person who performed the ritual and blind to all other past allegiances."

"Ah," Sam said, looking dejectedly over at Dean. "Well, that sucks..."

"If it helps, anyone using the Cup in such a manner can only use it on a willing subject; the warriors they create may not be fully aware of what will happen to them if their blood is added to the Cup, but they would have to be willing to serve the Cup's bearer to receive its benefits," Castiel explained. "It would enslave humans, but if used on a demon- a demon whose host had already been destroyed or consumed by the demon's presence within them-, the demon will be enhanced beyond all reason, immune to traditional methods of exorcism and capable of power on a level that only Azazel would have been able to match before now."

"Oh," Dean said, looking over at Sam with a grim expression.

They might have moved on since the days when the demon who killed Mary Winchester was their biggest problem, but he would always be remembered as one of their most dangerous adversaries; the thought of facing an army of demons operating on Azazel's power level...

"Well... we can stop it, right?" Sam asked, looking back at the angel. "I mean, we can empty the Cup-"

"The demons who have discovered it are already preparing rituals to elevate the Cup's power to a point where simply putting the blood in the cup will be all they need; keeping the blood in the Cup will just be optional," Castiel explained. "It is protected by anti-angel sigils so that we cannot retrieve it ourselves, and even if we did so many of the necessary rituals to change its nature have been completed that there is no place that we could hide it that would be safe from both sides; the only way to prevent the Cup from being abused further is to destroy it."

Sam had no idea how to feel about that.

He had vague memories of luring Cas to him by claiming to have found the Ark of the Covenant in a prayer at one point, and now the guy was telling them to destroy the cup of Christ (Or whatever its real history was, given his comment about how complicated the Cup's history apparently was)?

"Uh... Cas?" Dean said, looking awkwardly at the angel. "I know that we've had our ups and downs where your dad's concerned, but... I mean, destroying the Holy Grail-?"

"The situation in Heaven is too volatile for me to trust anyone with the necessary power to guard the Cup from others, and if it has been discovered once there is no reason to assume that the demons will not be able to find it again," Castiel explained, his tone excessively solemn even when the angel's usually near-emotionless nature was taken into account. "To prevent it from being misused once more, the Cup must be destroyed."

"OK, so... how do we do that?" Sam asked, swallowing slightly- they were talking about breaking the Holy Grail here, he thought he was allowed to feel uncomfortable- as he looked at the angel. "Is there a ritual, a weapon-?"

"There is a ritual, but it requires a very specific set of circumstances, one of which is the identity of the person who starts the ritual," Castiel explained. "There is only one person who has ever lived who possesses the power to destroy the Cup of Life, and we will have to contact him to enlist his aid in that endeavour."

"Who; Jesus?" Dean asked, smiling in amusement at the thought.

"Merlin," Castiel clarified.

Looking over at Dean, Sam was relieved to see that his brother appeared to be just as shocked at that news as he was.

"Merlin?" Sam repeated at last, trying to determine if Castiel was playing a bad joke of some kind. "Merlin was real?"

"As real as anything else we have encountered together," Castiel said, nodding at the Winchesters. "He was not what your popular culture has come to envision him as, but he was real, and he possessed a power and control of magic beyond anything any other witch or demon could hope to command."

"And... he was a good guy?" Sam asked, his mind lashing back to some of the witches they'd encountered over the years.

"His entire life was dedicated to defeating those who would use magic for evil purposes and using his own powers to protect those with none," Castiel solemnly confirmed.


"Oh," Dean said, stuck for anything else that he could say in this situation.

Even after he'd grown used to thinking of witches as something that should be hated and hunted for their allegiance to demonic forces, he'd always enjoyed hearing stories about Merlin and the Knights when he was younger; they were a chance to reflect back on the childish innocence of days when his mother had still been alive, when he'd been able to dream that they could just stop the demon and go back to the way things had been before...

To hear that they were real, that everyone he'd allowed himself to dream and hope about in those days of childish dreams existed...

"So..." he asked, pushing the part of himself that wanted to whoop for joy at the news that Merlin had been real aside in favour of focusing on the job at hand, "why do we need Merlin for this?"

"Merlin was the last person to fully master the power of life and death using the Cup of Life," Castiel explained. "Due to the power of the link he forged between himself and the Cup with that action, no other user can harness its full power unless he willingly grants it to them, and he never did such a thing when he was alive; having used that power once, he refused to do so again."

"Why?" Sam asked. "I mean, what's this stuff about the power of life and death-?"

"He attempted to save Prince Arthur from a fatal injury and his actions nearly resulted in the death of his mother and mentor when the Cup's power attempted to kill them to restore the balance," Castiel explained, his expression solemn as he stared at the Winchesters. "He rejected that power ever since in order to prevent himself endangering others- his control of the power of life and death to destroy his enemy to save his friend was only possible because of the intense emotions of the time, and he did not trust himself to make such a choice between ally and enemy again-, but he retains command of it, and therefore only he can begin the ritual necessary to destroy the Cup."

"So... what does that mean?" Sam asked. "You... find Merlin in Heaven?"

"No; rescuing a soul condemned to the Pit is possible- particularly in the case of those who made deals, as they may not have gone to Hell had the deal not been made in the first place-, but removing someone from Heaven without the approval of an Archangel would be all but impossible, even assuming I could determine where Merlin was, and bringing the Cup to Heaven for him to perform the ritual there would be impossible for more reasons than I can share now," Castiel explained, looking firmly between the two Winchesters. "To enlist Merlin's aid, we shall have to travel back to Camelot when Arthur was king and recruit him from that time."

Dean wondered what it said about him that he was more excited about the possibility of going to Camelot than he was concerned about the possible dangers posed by the scenario that Cas had just described to them.

OK, so demons had found the Holy Grail and were going to use it to create an army of uber-demons unless they could go back in time and work out how to perform a ritual that would destroy one of the most mythical objects in existence, but they were going to Camelot to meet Merlin; what wasn't cool about that?

Maybe he'd even get a chance to see a few of the knights in action into the bargain...