A/N: Actually not too many chapters left to go, now. Things will begin to heat up next chapter, and wrap up quickly from there. I hope you all will like what I've got in store to square this one off nicely – tell me what you think!

Merlin wasn't sure what to think about the fact that his older self knew the way to the Crystal Cave by heart.

They'd left Camelot without too much trouble. Although Merlin had been expecting some trouble getting his older self past the guards unseen, the older man had approached gates completely unfazed. Just as Merlin had about to voice his concern, his older self glanced at the guards and his eyes glowed. They lost interest at once, and didn't even question the destination of the two passers-by as they strolled out of the castle gates. Younger Merlin watched them curiously, and shot himself a questioning glance once they were beyond the gates. Older Merlin looked at him sidelong and grinned nervously.

"Attentive redirection," he explained. "Takes practically no energy, and they'll forget we were ever here. It's an addictive little trick. I'm trying to give it up." Young Merlin had to bite back a laugh. Currently, his older self looked like a boy who'd been caught stealing sweet tarts from the windowsill.

After that, their trek to the Cave seemed much shorter than it ought to have been. Merlin had been expecting trouble and dangerous beasts at every turn, as per usual for the Valley of the Fallen Kings, but it never came. Something about Older Merlin's presence made the Valley seem lighter than usual. Although Merlin was practically defenseless with his recovering magic, there was something about him that matched and defeated the gloom of the ancient fog, like he had conquered this place, that he'd claimed ownership here. Younger Merlin wondered quietly if he actually had.

"Here we are," Older Merlin's voice called from ahead, "don't fret yourself with the entrance down there, just follow me up to the top. Watch your step, though, it's a bit narrow." Merlin obeyed, and shortly found himself at the top of a mossy hill. A musical thrum greeted him from the direction where Older Merlin was headed, and he followed. The sound grew to a loud hum, and then a vibration in his chest that spread to his limbs, his head, until he was a wave of power and raw energy that reached out and brushed his magic with an electrifying jolt.

"What is that?" He asked, voice cracking from a sudden dryness. Older Merlin smiled.

"The magic in this tree is as old as the Cave itself," He spoke with great reverence, "but calmer, stable in this old wood." He set a hand fondly against the rutted bark. "We're old friends."

The tree itself didn't look like much. Trapped in beneath a suffocating canopy above, it hadn't grown very tall, and was gnarled in its old age, but its roots were thick with life, eating up at the ground and the magic steeped there. Merlin could feel pools of it beneath his feet, where the roots ran deepest. Older Merlin leaned himself down against the trunk to the ground and sighed contentedly.

"Yes, that's nice. Magic therapy, if ever such a thing existed. I'll just stay here a bit, if it's all the same to you." He closed his eyes and leaned back. Younger Merlin could understand why. The power radiating off of this place felt wonderful, he imagined it must be heaven for his older self, whose magic had been recuperating so slowly. Younger Merlin stepped quietly forward and set a hand on the trunk.

"What kind of tree is it?" He asked. He might've been able to tell normally, but the magic radiating from it was so strong, it distracted from the normal tell-tale signs.

"Elder," Merlin told himself. "the best kind, and solid with age. Perfect for conducting magic," He explained.

"Perfect for a staff, then,"

"Exactly." Merlin smiled.

Young Merlin nodded and rubbed his hand along a branch. "It's very smooth, for being so old," He said. Older Merlin grimaced.

"Aye, for the most part – save for that lightning strike in the back."

Merlin went around the tree and looked. "The what?" He asked confusedly.

"There's a huge charred strip there in the back, isn't there? Lightning, by the look of it. A mercy it didn't kill the tree."

Younger Merlin looked and shook his head. "There's nothing here," He said.

Older Merlin opened his eyes and craned his neck. "Isn't there?" He stood and came around to look over his own shoulder at the unblemished tree bark. "Oh. I suppose it must've happened sometime in the future." He looked at it, and shrugged. "at any rate, we'd best be at our carpentering if we want to leave here before I fall asleep against some old tree. Now." He stood up straight and Young Merlin followed the shift in mood. "We'll need you to perform the enchantment since I'm about useless these days. We just want to knock out a good length of wood, tall enough for a staff – can't take a blade this tree, could hurt it. Just a quick rush of magic to slice out our share. You'll repeat after me. Ready?"

"Ready," Merlin said, looking at the tree.

"Good. Right then: Ádón anbróce,"

"Ádón anbróce,"

"Fram æsc,"

"Fram æsc,"

"þacce,"

"Baccel,"

Older Merlin was already beginning to exclaim that he'd gotten the pronunciation wrong when a huge CR-CRACK, SNAP shot across the hillside and the two ducked for cover. When Merlin uncovered his eyes, there was a smoking, staff-sized slice of timber lying at his feet, and the tree itself was smoking as well. When it faded, he could see a long, charred section of bark and a deep black gouge into the tree. Younger Merlin began to apologize immediately, but Older Merlin wasn't listening. He was staring at the ruined bark with a shocked expression on his face. It took Younger Merlin a moment to realize that he wasn't upset.

"That's impossible," Older Merlin said to himself, almost a whisper. "That's… but…" He paused, and then his eyes grew impossibly wide.

"Merlin?" Young Merlin asked his older self cautiously. The older man continued to ignore him, having eyes only for the mark on the tree. It occurred to Merlin that the burn looked incredibly like a lightning strike. He blinked, realizing. Hadn't they just be talking about… but Older Merlin seemed to have already arrived at that point.

"Sweet Avalon."

Arthur had a horrible track record at subtlety, but luckily, when one was a prince in one's own castle, the call for subtle was forgiving, to say the least. Even when one was attempting to spy on someone else.

Of course, spying on yourself was another matter entirely.

Arthur had grown incredibly frustrated. He felt like he'd been strapped into a pair of blinders for the past two weeks, as a plot of research, time travel, and far more magic than he was comfortable with danced around him with the insistence of trust us, and you don't want to know. But he did. He was the prince, damnit, and he wasn't stupid. Whatever this… this fiasco turned out to be, hidden beneath all the escapades and 'research' and 'Merlin's not an idiot' mumbo-jumbo that he'd been spoon-fed for a fortnight, he could take it. He could understand. He wanted to. That's why he's started following his older self around after they'd had their chat about Merlin that morning.

The endeavor was a bit awkward, firstly because King Arthur himself had to go to some lengths to sneak around the castle unseen to begin with, whilst Prince Arthur had to make sure it didn't look like he was sneaking around his own castle, whilst simultaneously making sure King Arthur didn't see him sneaking around. It was a complicated process. They never prepared you for situations like this in strategy lessons.

As it turned out, Arthur must've developed some boring personality traits as he grew older, because the king took a leisurely amount of time roaming the hallways. To what end, Prince Arthur couldn't guess, but he was fairly sure he hadn't been spotted. Then, King Arthur had headed to the library, and began reading idly for several hours. Prince Arthur nearly fell asleep watching him, and thought about leaving twice, but eventually convinced himself to stay. He hadn't realized that his future self had been watching Morgana – who was sitting on the other side of the room, near the window – until Morgana got up and left near dusk. Older Arthur's eyes had immediately shot up and watched her. When she left, he set down his book and followed her casually. Something irate and shocked flared in Prince Arthur's chest. He was spying on Morgana? For heaven's sakes, why? He wanted to ask, but of course it would have made all this spying business irrelevant, so he didn't. He merely followed and watched.

King Arthur didn't follow Morgana for long. He watched her as far as the hall of her quarters, but once she'd closed the door behind her, he sighed and turned away. Arthur followed himself out into the courtyard, and then on to Gaius' chambers. He didn't follow inside, but stuck his ear up against the door.

"He's not back yet, then?" he heard himself ask.

"No. I'm sure they'll be along shortly. What of Morgana?" Gaius.

"Nothing to report. She reads a lot."

"The journal?"

"No. Just some book from Geoffrey's stores, so far as I can tell. She's gone up to her chambers." He heard himself sigh frustratedly. "It bothers me to think Guinevere is there with her. I wish I could get her out of there, somehow."

"On the other hand, Sire, Guinevere's presence should ensure that Morgana can't try anything overt without being noticed." Arthur frowned, wondering what on earth they were talking about.

"For now," King Arthur said. The Prince didn't like the low tone he was using – it sounded almost dangerous. The conversation died after that, but Arthur wasn't ready to leave. Quickly, he stood, thought, and knocked on the door.

"Come in," Gaius called. He opened the door and hoped he didn't look guilty.

"I've come to see if Merlin's back yet. It's nearly dinner time, isn't it?" He said, putting on an intentionally princely tone.

"Not yet," Gaius said. Arthur looked at him.

"I told you I'd let you know," He said amiably, the prince shrugged, not knowing how to respond to that. The King squinted at him, and Arthur was sure he'd just seen through himself. Ousted by yourself. How in blazes was that fair?

But he didn't get the opportunity to figure it out, nor did King Arthur have the time to call him out, because within a few heartbeats there were loud, stomping footsteps on the stairs, and two Merlins burst through the door, the older one looking wildly excited.

"I was wrong! I was wrong, so, wonderfully, completely, world-savingly wrong!" He was smiling ear-to-ear, and waving about a wooden stick in his hand, although Prince Arthur wasn't sure if Merlin realized that he was holding it or not. He stepped back slightly.

"Wrong?" King Arthur stood, "Wrong about – for god's sake Merlin, put your bludgeoning stick down and – what on earth are you smiling about?"

Merlin didn't seem to have heard him. "It wasn't there! But then it was, but of course it is now, but it wasn't! And it was just the same," He dropped his stick to one side, where younger Merlin caught it. "Arthur do you know what this means?" He grabbed the King by the shoulders and shook hard. Arthur seemed extremely confused as he said,

"You're not making any sense, Merlin,"

"We aren't changing anything!" the warlock burst out happily, and grabbed Arthur in a hug. Their younger counterparts were watching the scene with mixed confusion and discomfort. King Arthur stood still in Merlin's grip, unfazed by the embrace but still baffled by what Merlin had said.

"What do you mean, not changing anything? Arthur said around a cheek that was smashed by Merlin's arm, "you mean in time?"

"Yes!" Merlin exclaimed, and drew back. "I told you before that we were changing everything, that we'd be stuck here forever and completely ruin time and history as we know it," and as he went on grinning giddly, Giaus, Merlin, and Arthur all exchanged horrified glances. Obviously, they'd missed out on that particular conversation. Older Merlin continued on, "But I was wrong! So wonderfully wrong! He's proved me so, with a knotty old tree, bless it's charred roots!" Merlin pointed to his younger self.

"Alright," King Arthur said, in far calmer a tone than the Prince thought he would've been able to manage, "I think you'd ought to explain, Merlin, and start from the beginning."

Merlin visibly forced himself to calm down, but occupied his twitchy hands with fixing Arthur's collar and jacket, which had been tossed askew when Merlin had hugged him. The king let him, and watched the warlock's face expectantly, arms crossed.

"Arthur, you remember when you and I went up to that elder tree to get my staff the first time 'round, there was a huge scar on one side of it, like it'd been struck by lightning?" He brushed off Arthur's jacket shoulders as the king looked up in thought.

"Yes, I suppose there was. What of it?"

"Well, the strike wasn't there when Merlin and I went," He said, tugging down the corners of Arthur's collar, "Until, until we went to go get a piece of wood for the staff, and Merlin got the pronunciation wrong, and it was there!"

"Merlin," Arthur swatted his hands away, because in his excitement Merlin had begun to tug rather violently on Arthur's jacket, "what was there?"

"The lightning strike! It's just the same, but it's not a lightning strike – it never was! It's from just today, just now, when we got the wood to make our staff! It's the same thing!"

King Arthur was frowning. "From making a staff? That can't be the same thing."

"But it is!" Merlin insisted. Arthur shook his head.

"That's impossible. That was in our world."

"Exactly!"

"But that can't be the same unless…" The king's expression started to clear. "Unless it was there before,"

"Yes,"

"But that would mean that it was… today, you two," He pointed between the two Merlins, and the older one was beaming again and nodding his head.

"Yes!"

"And we didn't know about it until then, because you'd never been to that tree until-"

"Exactly!"

"But… Merlin, if that's all true, then that means,"

"We're not changing anything!" Merlin exclaimed. Arthur's face was full shock and revelation.

"We're… we're not changing anything," He said, and blinked, and slowly a smile took over his face. "We're not changing anything," He said, turning excitedly toward Merlin.

"I know!" The sorcerer was bouncing up and down for joy.

"Would someone please explain what on earth you two are on about?" Prince Arthur interjected, frustrated at his inability to understand. Younger Merlin crossed his arms and waited for the reply. Gaius was also watching expectantly.

As if noticing their company for the first time, King and Warlock looked about and tried to calm down. Merlin was still smiling widely, but was at least somewhat more civil as he said,

"By traveling through time, we're not changing anything. I thought we might have been, with disasterous results, but… we're not. It's all the same!" He said, "all of this, it's already happened. Do you know what that means?" He asked the air. Prince Arthur thought it was rhetorical, and raised his eyebrows expectantly, but it was King Arthur who actually answered, voice full of relief.

"It means we can go home."