A/N: And here we go...*dramatic drum roll*

**EDITED**

"What? Merlin, what are you talking about? Who is Lord Tennison?" Arthur demanded.

"He's the traitor in my court who's let Morgana into my kingdom," Merlin growled, red seeping into the edges of his vision.

He fumbled to pull his own transportation crystal from underneath his chainmail, his hands shaking in his anger. Merlin latched onto Arthur's arm with an iron grip and spat out the spell so quickly that he was vaguely surprised it didn't go horribly wrong.

The sensation of being spun at dizzying speeds and simultaneously sucked through a very tight tunnel with no air to be had was never a pleasant one, but Merlin had become accustomed to it since learning the spell a few weeks ago.

Arthur, on the other hand, had not had so much as a warning of what was to happen. As such, he pulled himself free from Merlin's grip the second their feet had slammed into solid ground and lurched away, looking as though he might be sick. He managed to hold onto the contents of his stomach, although he did throw a very nasty look over his shoulder.

"A little warning would've been nice, Merlin," he panted.

"Sorry, but we don't really have the time," Merlin said, too antsy to be very apologetic at the moment. He strode forward, looking for the Barrier.

He heard Arthur's gasp before he saw the telltale incandescent shimmer stretching from the forest floor up into the sky as far as he could see and further. It was the sort of thing that was hard to spot if one didn't know exactly what to look for, translucent as it was. It almost had the look of a gigantic soap bubble, but when Merlin pressed a hand to its surface, it was as solid and impassable as glass. Merlin reached out with his magic, letting it twine into the Barrier itself and join the thrum of power he and the Priests had placed there.

"Ábene þæt geat ætýnan ær mé," Merlin breathed out and the Barrier heeded his command.

The solid plane melted away beneath his fingers, a nearly imperceptible break in the smooth surface just large enough for the two of them to pass through. He turned to gesture to Arthur, who was a bit pale and staring up at the enormous dome with a rather awestruck expression. Merlin rolled his eyes—they didn't have time for Arthur to be overcome with wonder at his magic at the moment, he would have plenty of time to gape later—and tugged him through the gateway just in time for it to seal itself behind them.

"Sorry, Arthur, but you're gonna have to suffer through it one more time," Merlin said, taking up the transport crystal again, but Arthur promptly slapped it out of his hand. Merlin stared at him in affront, but Arthur was looking peeved and stubborn.

"No," he said firmly. "Not until you tell me what the hell that was all about. And what just happened." He jerked his head over his shoulder.

He still looked a little green around the gills, though he was steady on his feet; the nausea seemed to have passed, at least. Merlin was glad for that, really, and he would love to talk the afternoon away, but they just didn't have the time to waste with such things. Morgana was in his kingdom. Chances were she had transported straight to the city walls like he had intended to do before Arthur had put his metaphorical foot down. She could already be wreaking havoc in his city and Merlin wasn't there to put a stop to it.

"We don't have time for this, Arthur," Merlin snapped, reaching for the crystal again, but Arthur caught his wrist before he got there and held it.

"Merlin," he said.

The emphasis may have been the same as when he teased Merlin, the condescending sort of drawl that only Arthur could pull off, but the feeling behind the inflection was different. There was a worry that Merlin rarely heard there, an anxiety that only crept into his voice when he was going into a situation blind.

Which he was, Merlin recognized. He hadn't asked Arthur if he'd wanted to come with him on this. He could just as easily have left Arthur in his own kingdom, where a battle still raged, instead of dragging him along into another battle against someone he could hardly fight. With the danger he was putting Arthur in, Merlin owed him an explanation.

"That was a transportation spell," he said, trying his best to keep his impatience out of his voice. "It's not pleasant, I know, but you get used to it."

"And that thing?" Arthur asked, gesturing to the dome behind them.

"That's the Barrier. I mentioned it yesterday," he said. "It's a solid blockade that encompasses the main city for an hour in every direction. And it can only be opened by a handful of people, members of my council and my fighting force."

"What happened back in the throne room?" Arthur pressed. "Morgana had one of those charms you gave me. Then she disappeared and you just sort of froze, I couldn't get a word out of you."

Arthur would probably deny the concern in his voice but Merlin heard it clear as day and it made him squirm with guilt again to know that he was making Arthur worry so.

"You're right, Arthur. She had that charm and she also had one of these." Merlin held up his transportation crystal—by the string so that Arthur didn't think he was trying to transport away and knock it from his hand again. "I invented this myself and I've been overseeing their production. She had no way of getting her hands on either of these things."

"Unless she had someone on the inside," Arthur provided. "You said that someone had let her in."

"Lord Tennison," Merlin said through gritted teeth. "He has access to the new innovations of the High Priests, he has the authority to open the Barrier, and he's had a serious grudge against me since day one."

"Why?" Arthur asked, looking thoroughly confused as to why anyone would bear ill will towards Merlin. That made Merlin roll his eyes, though a fond smile made its way onto his face anyway.

"Because he thinks I usurped his son," Merlin said.

"Why would he think that?" Arthur asked, even more bewildered.

"Because I sort of did, in a way. Lord Ellison is my second cousin. And the council was willing to turn the kingdom over to him if Sir Gerund's search for me didn't pan out."

"Oh. Yes, I guess that would do it."

"Everything else can wait until later," Merlin insisted. "Morgana's likely already wormed her way into my castle; it wouldn't be hard with Tennison at her side. Sorry about this, but there's no other way to get there quickly."

Arthur groaned as Merlin took up the crystal once more but didn't complain as Merlin grasped his arm. He managed to maintain his balance upon landing this time, though he still looked a tad sick. But he just shook his head to clear it and gestured for Merlin to lead the way.

As soon as the main gates opened to admit him, a blue-clad figure was rushing towards him. Merlin didn't stop to meet him.

"Sir Galahad, report," he said and the knight turned hastily to fall in step with him, mirroring Arthur's position a half-step behind him.

"It's the witch, my Lord. She has breached the citadel," Galahad said.

"Casualties?" Merlin asked, dreading the answer.

"None that I know of, sire," Galahad answered to Merlin's surprise. Merlin's sidelong glance prompted him to explain. "She was very focused on her goal. She wasn't fighting, simply getting people out of her way. There are a plenty of injuries, but no fatalities so far."

Merlin nodded, relieved.

"Let's see that it stays that way," he said. "No one is to engage her. She is far too powerful, especially in her current state. She has nothing left to lose and that makes her dangerous."

Sir Galahad nodded. "Sire…" he said, though he sounded reluctant to voice his thoughts. "She could not have broken through the Barrier herself."

"I know, Galahad. Not even I could manage such a feat," Merlin said.

"But that means that someone had to—"

"Lord Tennison has committed treason," Merlin interrupted him, his tone unforgiving. "And he will be dealt with accordingly."

Galahad remained silent for a moment as they stalked past a group of slumped figures in blue cloaks, a few servants with cloths and bandages scurrying among them and attempting to bring them around.

"Sir Galahad, give the order for the Barrier to be sealed," Merlin ordered. "No one is to travel in or out of the city until the situation is under control. Then you are to take a patrol and scour the city. It is unlikely that Tennison smuggled in any other hostile parties but it is not a risk that we can afford to take."

"Yes, sire." Sir Galahad gave him as much of a bow as he could whilst walking so quickly and then turned back toward the gates to relay the instructions he had been given.

Merlin led Arthur up the steps and into the palace proper, making his way through the wide, winding corridors with an ease and familiarity than belied how lost he had become in his first week or two.

Arthur kept pace with him but remained a step behind. Merlin wondered briefly if that was out of propriety, an acknowledgement that he was in Merlin's kingdom and therefore Merlin's status was technically superior to his, or simply because Merlin was leading the way. He didn't have much time to think on it before they neared the throne room.

Much like in Camelot, the guards were no longer standing at their posts but slumped on the ground, though Merlin was relatively certain that his guards, though unconscious, were still alive. The doors had been left open and the voices of those within met Merlin's ears long before he and Arthur reached the entrance.

"Father," came Ellison's voice, shaky and uncertain. "How could you do this? How could you let her into the kingdom?"

"It is for the best, Ellison," Tennison insisted.

"It is treason!" Ellison shouted back.

"With the Lady Morgana's help, you will be restored to your rightful place upon the throne," Tennison said with the fervor of a fanatic.

Merlin quickened his pace, Arthur hastening along in his wake.

"Once she has taken Camelot, Carthis will be yours to rule. As it should be."

"No, father," Ellison said, and Merlin reached the doorway in time to see him pull his arm out of his father's grasp and stumble backwards.

Morgana stood to the side, watching the family spat with a bored sort of amusement.

"I don't want to rule," Ellison told his father. "Merlin is—"

"That boy is a disgrace," Tennison snarled, advancing on his son. "The peasant son of a coward and a fool. A bastard and a usurper, not fit to lick the dirt from your boots!"

"Merlin is a good man!" Ellison said fiercely. "And a better king than I could ever be. I'm sorry, father, but I will not depose him, no matter the power you offer me."

Morgana didn't look so amused anymore. Her expression turned cold and she stepped between the two men, leveling her sharp gaze on the one standing in her way.

"Step aside, Ellison," she said coldly. "I have no desire to harm you, and I will not do so unless you give me reason to."

"Ellison, think about what you're doing," Tennison implored him from over Morgana's shoulder.

Ellison looked between them, torn between horror, fear, and indecision. But one more glance told him all he needed to know: his father would not be persuaded from this path and Morgana would not take no for an answer. His features hardened into a mask of defiance.

He raised a hand and threw a burst of energy at Morgana. She blocked it with ease, so he drew his sword from the scabbard at his hip and lunged at her with a cry. Merlin knew immediately that he would not complete the attack.

Merlin's feet were moving before his thought was complete but he wasn't quick enough. Before he was even fully into the room, a swipe of Morgana's hand had sent Ellison crashing into a pillar. He slumped at the base of it and did not move, his sword falling from limp hands to clatter onto the stones and blood welling from his temple. To Merlin's surprise and dismay, Tennison was not the first person to reach the fallen Lord.

Raime darted out from behind the pillar and dropped to his knees, pulling Ellison's head into his lap to examine the damage. Tennison crashed to the ground beside him a second later, panic on his face as he looked upon his unmoving son. Raime caught sight of Merlin in the doorway and his anxious expression cleared immediately.

Tennison followed Raime's gaze and he was not nearly so relieved to see him. On the contrary, he leapt to his feet and drew his own sword.

"You!" he bellowed. "This is your fault!"

He looked quite mad, his red face contorted in rage and grief, and he launched himself at Merlin with an incoherent cry. Before Merlin could so much as raise his hand to cast a spell in self-defense, Tennison jerked to a stop as the tip of a sword protruded from his chest. Tennison coughed, flecks of blood flying from his lips, and slumped to the ground. Left in his place was Raime, pale and nauseous-looking but steady on his feet nonetheless.

They all stared at him in shock and he stared back, equally stunned by his own actions. He dropped the sword and the clang of it hitting stone echoed loudly in the silent chamber. He took a stumbling step back, looking from Tennison's body to Merlin and back again, trying to comprehend the sight before him. Before he had wrapped his head around it, Morgana spoke.

"Pity," she said lightly, looking down her nose at where Tennison's blood was pooling around him. "He could still have been useful."

With that, she conjured a ball of flames in the palm of her hand and flung it toward Raime. Arthur leapt forward to snatch Raime out of the way and the projectile crashed into the wall, setting one of the blue hangings alight. Merlin threw out a wave of magic that Morgana blocked just in time and risked a glance back to make sure that Arthur and Raime were safely ensconced behind him.

"I thought I told you to stay out of the fighting, Raime," he said, exasperated even as he redirected another of Morgana's fireballs.

"No, you told me to stay in Carthis," Raime pointed out, rallying from his shock. "Which I did. And good thing, too. I just saved your life."

Merlin gritted his teeth and threw up a shield against Morgana's attempt to cut him in half with a nasty slashing spell.

"I could have taken care of Tennison."

"And fought Morgana at the same time?"

Merlin tried to pull Morgana's feet out from under her but she forestalled him with another dizzyingly strong knock-back spell.

"Fine, then. I could have taken Morgana and Arthur could have taken care Tennison," he ground out.

"Well, now neither of you have to take care of him because I took care of him for you."

"Gods above, was I this bad as your manservant, Arthur?" Merlin growled.

"Ten times worse," Arthur said, and he had the gall to sound amused. "But perhaps you can save this conversation for later?"

Right on cue, Morgana let loose a raging inferno, fire spewing from her fingertips to fly the distance between them. Merlin raised both hands and braced himself, the words he needed coming readily to his lips.

"Smiðe lígϸraca into gicelum." The flames froze under the force of his magic, coalescing into shards of ice that hung in the air before him. He turned them around with a wave of his hand and sent them careening back toward Morgana.

"Ámyltaϸ," she cried, and the icicles melted. "Ábeateaϸ hine." The water swept toward Merlin with the force of a tidal wave.

"Úpáwæl," he said. The wave boiled and hissed before evaporating, a cloud of steam washing over him harmlessly. "Ástrice."

Morgana blocked the spell and responded in kind. The two of them blocked and parried and dodged, too evenly matched in skill and experience for either of them to make any headway. Merlin didn't notice Arthur creeping around him until he was already raising his sword in hopes of striking Morgana down while her attention was otherwise occupied.

Arthur charged toward her. Morgana batted the sword from his hand with a wave of her own and conjured another ball of flames, a gleeful snarl on her face at the chance to put Arthur down for good.

Merlin called out a spell and yanked Arthur backward, out of harm's way. Arthur stumbled to a stop behind him and immediately shouted a warning. Merlin barely had time to throw up his shield before Morgana's attack slammed into it.

The force of it pushed him back a step, tendrils of Morgana's dark magic lapping around the edges of his own, but his shield held strong. Merlin hastily wrapped the shield into a dome, pulling it in tight around them and bracing himself for a lengthy siege.

"Arthur, are you alright?" he asked without looking back.

"I'm alright," Arthur said. "Are you?" He sounded worried.

Morgana was throwing spell after spell at Merlin, hammering at his defenses. Every assault sent magic flooding across Merlin's own, seeping past to skitter and dance along his skin, and every retreat dragged heavily along his shield, catching and pulling until Merlin had to fight to hold it where it was. He placed a hand against the inside of his shield to strengthen his connection with it. Sweat dripped into his eyes but Merlin didn't have the luxury of wiping it away at the moment; he needed all of his concentration.

"I'm fine," Merlin said.

It came out breathless and strained, which probably wasn't very convincing. He could practically hear Arthur's skepticism and worry, and a quick glance over his shoulder confirmed his expression.

"Magic isn't an inexhaustible resource, even for me," he admitted. "And I've already used a whole lot of it today. Morgana's an incredibly powerful sorceress—" Merlin winced as a particularly strong blast proved his point. "—and she hasn't been expending nearly as much energy as I have."

"In simple terms, please."

"I'm tired and she's not," Merlin bit out. "Normally I can let people wear themselves out trying to break through my shields—no one's ever managed it—but I don't think that's an option right now. I need to end this, and soon."

"Come now, Emrys, don't cower," Morgana called out, her drawling voice audible even over the cacophony of clashing spells. "Come out and face me. You can't hide behind that shield forever."

Another hard blow made Merlin wince and then scramble not to allow his own magic to be drawn out as hers retreated. It was an exhausting dance of push and pull.

"Options, Merlin, what are your options?" Arthur prompted, a solid, grounding presence at his back.

Merlin took a deep breath and took stock. His hands were trembling from the strain of standing firm against Morgana's onslaught. His magic was flagging, worn down and drawing thin, and he breathed deeply again to calm himself and shore up the weak spots in his shield.

"Face it, Emrys," Morgana taunted. "I am a High Priestess of the Old Religion. You cannot defeat me."

Morgana wasn't leaving him an opening to strike back. With his abilities and the techniques he had developed, that didn't mean he was out of the running, but after so much fighting he just didn't have the reserves necessary to split his focus to attempt a second spell that wouldn't siphon its power from his shield. To try and attack now would be to risk exposing himself and, more importantly, Arthur and Raime.

Then his eyes fell on Arthur's sword, abandoned on the floor a few steps behind Morgana. His heart rate sped up. If any weapon could kill a High Priestess, that one could.

Morgana let loose a barrage of pure magic and Merlin felt it like a physical blow. It nearly sent him staggering, while the magical riptide pulled him in the opposite direction. Raime called his name in alarm and Arthur gripped his arm to steady him. Merlin shook him off and reached for his transportation crystal. It still had some power, and the thrum of it under his fingers was like a breath of fresh air. He didn't need to be at full strength to split his focus if he was drawing the energy for the second spell from a different source.

"You two stay here," Merlin said, as if they could do any different. He gave the dome one more thick wash of magic, all that he had left in him, to bolster and secure it before dropping his hand from its glittering surface. "The shield will hold."

Arthur started to ask what he meant to do, but Merlin was already incanting.

In a whirl of wind, he was halfway across the chamber. Morgana continued her attack on the golden dome shield without realizing that Merlin was no longer inside it. Merlin crept behind her, keeping half an eye on his shield to make sure it was stable, still feeling the push and pull of maintaining it even from a distance, until he could grasp the hilt of Arthur's sword. The magic in the blade leapt up to greet him, welcoming his familiar presence.

The light scrape of metal against stone as he picked it up drew Morgana's attention. She spun to face him, deadly words on her lips, but Merlin met her halfway. The sword sank into her stomach before she could finish her spell and she cut off with an "oh" that sounded too delicate for the violence of the act. A deranged grin spread slowly across her face.

"Nice try, Emrys. No mortal blade can kill me," she said. She coughed and blood flecked her lips.

Merlin shook his head, pity making his heart clench painfully in his chest.

"This is no mortal blade," he told her. "It was forged in the breath of a dragon."

He twisted the sword and Morgana let out a choked cry. Her grin faded and panic lit her eyes behind the madness. Her fingers scrabbled for purchase on Merlin's armoured chest and found none. Her knees gave out and Merlin cradled her as she fell. She gasped for breath and coughed again, leaving a froth of red that recalled the lip paint she had been so fond of as a lady of the court. Merlin pulled the sword free and Morgana fell still, her eyes dimming as she breathed her last.

Merlin dropped the sword and laid her out properly. He met her eyes once more and then gently closed her lids. It was over. He wasn't sure what he had expected to feel in this moment of triumph, but all he felt now was tired. Arthur's hand on his shoulder startled him; he didn't remember letting the shield fall, but it hardly mattered now. Arthur knelt beside him and they bowed their heads, paying their respects to the woman she had been, back when she had been their friend.

"Sire," Raime called, and Merlin raised his head. His manservant was kneeling over Lord Ellison again and gesturing him over.

Merlin squeezed Arthur's shoulder and left him to mourn his sister. Ellison was struggling against Raime, trying to sit up, but Merlin gently pushed him back down again.

"Lie still," he said. "You took a nasty blow to the head. You'll need to be looked over by a healer."

Ellison blinked up at him, confusion etched on his features before remembrance set in.

"Morgana!" he said abruptly. "The Lady Morgana was here. My father, he let her in. You need to—"

"Shh, Ellison. It's taken care of," Merlin assured him. "The Lady Morgana is dead. We don't have to worry about her anymore. The kingdom is safe."

Ellison strained against his hand for another moment before the words sunk in, and then he collapsed back onto the floor, eyes closed in obvious relief. Merlin took the opportunity to gesture for Raime to fetch the healer, and the boy nodded and left the hall quietly.

"My father," Ellison said weakly. He sounded deeply tired, the sort of weariness that went beyond the physical. Merlin knew the feeling well. "He is a traitor. He let her in."

"I know," Merlin said softly. "I'm sorry, Ellison."

And he was, in much the same way that he had been sorry for Agravaine's death. Not because of any sort of respect or affection for Agravaine, but because his betrayal and his death had hurt Arthur. This time, when Ellison shifted, Merlin helped him into a sitting position. Ellison's eyes fell on his father's body and he stared for a long time.

Merlin left a hand on his cousin's shoulder but didn't say anything. For all that he had betrayed the both of them, Tennison had still been Ellison's father, and the bond of love between father and son could not be so easily shattered. Ellison bowed his head and took an unsteady breath.

Merlin was saved from having to break the silence by the return of Raime, a young woman in long robes at his heel that he knew to be called Esla. She was one of the Court Healer's apprentices, already quite skilled in her own right and left to tend the city while the rest followed the army to Camelot, and Merlin gave her a small smile as she knelt down at Ellison's other side. She touched Ellison's back and began murmuring questions to him, assessing his condition as gently as possible. Merlin left her to it.

He stepped out into the corridor and flagged down a passing guard. He explained what had happened, that the traitor had been found and the threat nullified. He ordered that the Barrier be left in place for a while yet, at least until things had calmed down and everything had been secured. Then he sent the guard in search of someone who could dispose of Morgana's body, and Tennison's, with respect. The guard nodded solemnly and hastened to his tasks.

Merlin turned back to Arthur and Arthur stood to meet him halfway across the chamber. Arthur didn't say anything at first, looking as heavy as Merlin felt, and Merlin ran a hand over his face.

"Now what?" Merlin asked.

"We must get back to Camelot," Arthur said. "The battle was still being waged when we left."

Merlin winced, reaching for the transport crystal around his neck. It had barely a flicker of power left in it, not enough for even one transport, and he wasn't so sure he had the power to get them anywhere right now. They would have to go back the old fashioned way, which meant three days on horseback, unless he could borrow someone else's crystal.

Merlin strode back to Morgana's side and hesitated only a moment before kneeling beside her and searching for the pocket of her dress. He pulled free her transportation crystal. The magic inside felt slimy and dark, and his own rebelled against it on instinct, but it would do well enough to get them from point A to point B. Arthur didn't comment on his usage of it.

Merlin didn't notice until they were halfway through the lower town that Raime had fallen in behind them. He opened his mouth to send him away but, recognizing the stubborn jut of Raime's chin as reminiscent of his own, he just closed it again and shook his head.

The people they passed on the street whispered to each other, the news of the battle and Merlin's triumph spreading quickly. No one approached them, but a number of people bowed low as Merlin drew even with them, many of the druids going so far as to kneel and press their foreheads to the ground. Merlin nodded to each of them, too done in to be overwhelmed by the awe and reverence in their expressions. Sir Galahad simply nodded to him at the city gates and Merlin tried his best to smile.

Once the gate had shut behind them, Merlin held out his arm. Arthur and Raime both laid hands upon it. Merlin grasped Morgana's transport crystal and muttered the spell that would take them away.