Sensitive Content Warning: (post) emotional torture and a panic attack

Also: let's pretend the dark tower room Gwen was in was a little different / Merlin was in an other room

Time: between the end of 5x06 and beginning of 5x12

Merlin in the Dark Tower

Arthur had never come across such a heavy door. While Percival was fighting the two guards, Arthur gathered all his strength and pressed his back against the door that probably never opened more than a few inches. When he finally managed to push himself through the gab, the door shut close and Arthur couldn't see a thing. "Merlin!", he whispered. Silence. But not only didn't he get an answer, he realised; there was nothing to hear at all. Busy Camelot was always noisy and even in the woods there were always animals breaking branches, birds singing and wind making the trees rustle. Now, he couldn't even hear the sound of the swords clashing together on the other side of the huge door. Arthur looked around, hoping his eyes had adapted to the dark by now. But he still wasn't able to see anything. He smelled wet soil, but didn't perceive any other scents. Arthur reached out and eventually touched the cold stone wall. Should he start walking along the wall even though he had no idea how the room, well it was more of a dungeon cell, was shaped? Would he be able to find the door afterwards? But he had to find Merlin somehow. Just when Arthur took his first step, the door opened a slice. Relief to see at least some light flooded him. Of course did Percival defeat the guards. It was still too dark and the room was huge and had a lot of pillars that blocked Arthur's view as well. "Percival? Get me a torch." Percival stopped pushing and the door fell back immediately. Darkness. Although he had only spend a few minutes in this room, Arthur hated it. He just wanted to find Merlin and get the hell out, so he could rely on his senses again. The door opened again and Percival managed to throw the torch in with one hand and keep the door open wide enough with the other one. Arthur picked up the torch and took a look around. In front of the wall at the far back of the room he saw a figure lying on the ground. Merlin was curled up into a ball, his forehead nearly touched his knees and he had both hands pressed on his ears. "Uggh." Percival had finally managed to squeeze through the door as well. Arthur hurried to his so tiny looking friend. "Merlin!"
"No, no..." Merlin mumbled.
"Merlin, it's me."
Merlin lifted his head just a little, so he could peek over his knees. "No... No! Get away from me!"
Arthur froze. He last thing he would have expected was his rescue mission ending in Merlin shouting at him. "Merlin – "
"Leave!" If looks could kill, Arthur would be a dead man.
"Don't be stupid."
"Leave. Me. ALONE."
"Merlin, we need to – " Before Arthur could finish his sentence, Percival had walked pass him and knocked Merlin out.
"Percival!"
"Sorry, but someone had to. Like you were about to say: we need to get out of here."

In less than half an hour later they had made it out of the tower. Arthur knew Percival for a while now but he still got impressed by his strength once in a while. Without him to hold the door open, Arthur wouldn't have been able to carry Merlin through. Percival was limping with a bleeding leg from the fight in the tower as they walked away from the tower. Arthur was panting from Merlin's weight on his shoulder, but he was much lighter than Arthur had in memory. Apart from his weakness, Merlin didn't seem too badly hurt. A couple of bruises and half healed cuts, but they all have had worse injuries. He's gonna be fine, Arthur told himself. He tried not to think about the fact that Merlin didn't want to see him and had sent him away. Merlin probably just wasn't thinking straight. The three reached the rubble trench, which the knights had appointed as assembly point when they split up. Percival ended up more or less sliding down the wall, so Arthur decided not even try getting Merlin in the trench unconscious and put his limp body down. Percival searched the bags, that they had left hidden there before going into the tower, for bandages. Arthur asked him for the waterskin and Percival threw it up. As the next river was in the forest, he didn't dare to waste to much water, but he sprinkled a little bit on Merlin's face, and it was just enough to make Merlin open his eyes. He saw Arthur and jerked, he quickly sat up with his brows pulled together, lips pressed together.
"Merlin, it's alright."
"No!" Merlin blocked his own view with his arms. "Go away!"
Arthur grabbed and lowered Merlin's arms. Arthur would have continued talking but the sudden surprise written all over Merlin's face stopped him. Merlin was starring at him, then looked around and then at Arthur's hand on his arm. Arthur let go. But before he was out of reach, Merlin had already grabbed his wrist.
"You're real?" It sounded like a question.
"Course." Merlin kept starring at him and squeezed Arthur's writs so tight that he wasn't sure if his blood was still flowing like it was supposed to. "I'm real, I'm real", Arthur assured quickly.
"Thank god." Merlin pulled him into a firm embrace.
"Seems like someone is very glad to see me." Arthur expected Merlin to shoot back a denying response, a joke, but Merlin just replied quietly: "You have no idea."
Arthur finally wrapped his arms around Merlin's back. That's right, he did have no idea what Merlin went though in the tower. The imagine of Merlin in the dark, in the cold, curled up like an embryo, popped back into his mind. "Sorry", Merlin said and pulled back from the hug.
"I'm gonna get you something to eat." Arthur stood up and gave Merlin the waterskin. He took a step but then looked back at Merlin, who was practically chugging down all of the water in record time and ended up coughing. Merlin met Arthur's glance and awkwardly lowered the waterskin. "I'll take a look for some more water too", Arthur said. Merlin didn't really know what to answer and Arthur went down the precipitous wall.
Percival was inspecting his arm and then ripped of a piece of cloth. Arthur hadn't even noticed the cut before, only the one on his leg that was perfectly bandaged now. "Let me." Arthur took the cloth away and tied it around Percival's arm. "How's your leg?"
"It's fine."
Arthur nodded and pulled bread out of one of the bags. "You did a good job back there", he said. Percival nodded with appreciation. Next to him, Arthur spotted Percival's waterskin, with what he probably cleaned his two wounds with. "You wouldn't happen to have some water left, would you? We've got very thirsty friend up there."
"He's awake? Yeah, sure, go for it. How is Merlin?"
"He's... better I guess. He doesn't hate me anymore. Well, not more than usual."
"That's good." A heart beat later Percival added: "I'm sure, he'll be fine."
"Of course he will", Arthur replied. He didn't want to seem worried. But Percival's optimism did make him feel a little better when he climbed back up the trench wall.
For the first time since they had found him, Merlin smiled at Arthur. Well, he smiled at the bread. "Mmm", he said with the first bite. "That's the best thing I ever tasted."
Arthur chuckled. But then his smile faded. "How long haven't you eaten?"
"They gave me food every like... two or three days. I don't know, it's hard to tell the time in there." When Merlin saw Arthur's face, he quickly added: "But I got water everyday." Arthur nodded.
Suddenly he heard something and spun around.
"Are you getting slow, princess?", Gwaine said. He and the other knights were only a couple of meters away, all looking a bit damaged. "Oh thank god." Gwaine had spotted Merlin. As he passed Arthur, he gave him a pat on the shoulder. "Good to see you in one piece, Merlin."

A while later they were heading to the forest on their way back to Camelot. Merlin was walking alongside Arthur at the end of the group. For the first time in a long time Merlin didn't have to carry anything. His eyes hurt and he had to really concentrate to not just shut them and fall asleep. Arthur was quiet but he was walking close and Merlin noticed his glances whenever the ground was rough and uneven. The sun was already starting to set when Arthur asked: "Why you? What did they want from you?"
If Merlin wasn't so tired he would have panicked and probably come up with a good lie. Obviously he couldn't say the whole truth but he was so drained that he stayed as close to the truth as possible. "They had two dragon eggs."
"Dragon eggs! I thought all dragons were dead", Arthur interrupted.
"Apparently they're not. They wanted me to make the dragons hatch out." Arthur raised his eyebrows but let Merlin continue. "If a dragon lord gives a dragon a name, it hatches out. I told them they had the wrong person but they wouldn't listen. They told me they'd put me in the dark room until I stopped lying and help them."
"They thought you were a dragon lord?" Arthur made a noise somewhere between a huff and a chuckle. "How did they get that idea?"
"Probably a misunderstanding I guess. Maybe they got told that Gaius knew a dragon lord. But Balinor was the last one."
"So they won't hatch? The dragons are save?"
"Yes they are. But as long as they have the eggs... I have no idea what these people will come up with."
Arthur nodded. "We'll get the eggs to safety as soon as possible, but we need to plan the attack carefully. You heard the knights, those guys were tough."
"Since when are you making wise decisions?"
"Since always, Merlin, I'm the king. That's what I do."
Merlin smirked but at the same time he tripped of his own feet because he didn't pay attention to them anymore. Thanks to Arthur's fast reflexes he didn't fall. Arthur didn't say anything but stopped walking and looked around. "It's getting dark and I think we're far enough away from the tower", he said and shouted: "Leon!" The knight turned around and Arthur drew a horizontal circle in the air with his index finger. "Camp!" Leon heard him or at least knew what he meant and instructed the other knights.
"Shouldn't we get as far away as possible?", Merlin asked.
"Most of the men are injured and I think they killed enough that they are probably outnumbered now. If one of us keeps watch over night, we'll be fine."
"I can take the first shift." Arthur shook his head. He knew Merlin only wanted to help but right now the only thing he needed to do was to look out of his own well-being. "You", he said determined, "will sleep."
After they had walked up to the rest of the group, Arthur helped collecting fire wood, while Merlin just sat down and leaned against the only tree in sight, a half-dead, leaf-less and very dry one. He stopped starring into the distance when Arthur approached him and waved his hand in front of Merlin's face. "You still among the living? Honestly, I have no idea how you manage to keep those eyes open."
"I'm fine", Merlin said but already knew it wouldn't stop Arthur from taking.
"You need to sleep."
"I can't."
"Of course you can."
"But I don't want to."
Merlin immediately realised he said a bit too much, he could basically see Arthur thinking and letting this statement sink in. He sat down next to him leaned against the tree as well.
"Do you wanna talk about it?" Merlin shook his head. For a moment they both just watched the knights warming up around the fire and settling in for the night. "Okay", Arthur eventually said. Then he chuckled as he thought of something. "You know, on our way to the tower we started talking about relatives somehow and I had this really sniffy, annoying aunt. She used to visit us a lot when I was young and I hated her. Did I ever tell you about her?" Merlin shook his head again and Arthur started telling stories about her. He had been such a prat back then but this arrogant aunt definitively deserved it. The stories made Merlin smile and took his thoughts away from what had happened this week. Whenever Arthur finished a story, he though of something else, childhood stories that didn't have anything to do with this aunt anymore, and Merlin was very grateful for that. At some point he didn't listen to the words anymore, but it was good to hear Arthur's happy voice, knowing he was fine.

When Merlin fell asleep, Arthur told Gwaine to wake him up for the next shift and went to get some rest as well. He laid down by the fire and wrapped himself up in his cape. He listened to the soft snoring of the knights but it took him a while to catch some sleep himself.
It wasn't Gwaine that woke him up later, it was a strange panting, grasping sound. Arthur immediately sat up, on alert like always in the woods, and his eyes found the silhouettes of Gwaine and Merlin. From his posture Arthur could tell it was Merlin who was constantly taking in gulps of air. Arthur rushed up ad to them. Apparently Gwaine's attempts to calm Merlin down weren't working, so Arthur pushed him aside a little so he could stand directly in front of Merlin and look him in the eyes. He placed his hands on Merlin's shoulders. His friend wasn't in control of his body, he was convulsing and sobs violently shook this whole body. "It's alright, it's alright. Look at me. Listen, breathe out, okay?" Merlin was trying to but struggled. He was starring at the ground to focus. "Breathe out. That's how you'll get air, breathe out. Look, I'm here. I'm here, it's alright." Merlin looked up and just forgot to suck in as much air as possible. "That's it, that's good." Air gently flooded Merlin's lungs and he breathed out again. "Here you go." Merlin grabbed Arthur's arms with both hands and squeezed them tightly. "I'm here", Arthur repeated calmly, and suddenly remembered Merlin's question from earlier. "I'm real. I'm real, alright? I'm not going anywhere. I'm here." Merlin nodded, still shaking but his breathing was much calmer and he had stopped crying. He let go of Arthur's arms and Arthur pulled him in a hug. "It's alright." Merlin laid down his forehead on Arthur's shoulder. Arthur's eyes met Gwaine's, who had given them some space but was still watching them. The knight gave Arthur a nod, turned and walked away to the others. Arthur was facing the other way, but he was sure most of them had woken up too.
After a while Merlin stopped shaking. He lifted his head and quietly said: "You died. That's what I saw. Over and over again you died, suffering, in agony. I had sworn to protect you or die at your side. But I failed." Arthur let go and opened his mouth, even though he couldn't catch a clear thought to say. He didn't get the chance to either, because Merlin said: "But it's alright now. I will not see that again. I'm not gonna let that happen."
Merlin walked away and left Arthur speechless.

They both never talked about what happened that night or in the dark tower ever again. But it changed them.