“You killed Nimueh?” Arthur asked in disbelief.
Merlin winced. “Did I not mention that before?”
Arthur shakes his head numbly.
“Must’ve slipped my mind.”
“But- but how?” Arthur sputtered. “Why?”
Merlin sighed. “That's a bit of a long story,” he said. Arthur raised his eyebrows, so Merlin continued. “Right. To summarize, Nimueh and I made a deal. Then she double crossed me, and so I went back to her, and she tried to kill me. She hit me with a fireball in the chest, so I got mad and conjured lightning to strike and kill her.”
Arthur gaped. “You can summon lightning to kill people?”
Merlin rubbed the back of his head. “Yes, I suppose I can. I don't do it that often, though, if that makes you feel any better.”
Merlin shrugged. “I tried.”
“Hang on. Why would you be making a deal with Nimueh?” Arthur asked with a frown.
“That's the part that you might not want to hear.”
“What part of that did you think I would want to?” Arthur retorted.
“Well, this is the part that you really don't want to,” Merlin stalled.
“Spit it out. I want to know why she would try to kill you,” Arthur said, not even slightly dissuaded.
Merlin looked confused. “Oh, no, her killing me was part of the deal.”
“Yes, I… suppose I forget to tell you that bit.”
“Merlin. Explain,” Arthur snapped.
“Right. So, do you remember when you were bitten by the questing beast?”
Arthur’s face darkened. “How could I forget?”
“Right. So you didn't exactly completely survive on your own?” Merlin told him hesitantly.
“Of course I didn't. Giaus helped me. He gave me a medicine that saved me,” Arthur responded. Then he frowned. “That's not what you were talking about, was it?”
Merlin shook his head, looking down.
“What happened that I don't know about? Did you use your magic to save me?” Arthur asked, wondering why Merlin seemed so hesitant to tell him the truth.
“Not quite. I tried, Arthur, I swear, but there was nothing I could do. So… I went to the Isle of the Blessed to find Nimueh. I made a deal with her to bring you back to life.”
“How on earth did you do that?” Arthur asked, beginning to understand but desperately hoping to be wrong.
“I traded my life for yours,” Merlin told him simply.
Arthur processed this for a moment before exploding, “and why the hell would you do that, you bloody idiot?”
Merlin looked mildly surprised. “You were dying, Arthur. There was no chance of saving you. The kingdom needs you.”
“And I need you!” Arthur snapped. Then he looked confused. “Wait a minute. The things you told me that night… you weren’t just being strange, were you? You thought that would be the last time you were going to see me. You thought you were going to die.”
Merlin nodded, not looking at all regretful.
“And you weren’t even going to let me say goodbye? You said everything you needed to, but I had no idea that I would never see you again! I just told you that you couldn't talk to me because I was a prince! How do you think I would feel if those were my last words to you?”
“Better than you would feel if you were dead!” Merlin snapped.
“You don't know that!”
“Why are you so surprised? Did you think you just happened to recover from an invariably fatal bite? And did you honestly believe that I would have let you die?”
“No. But you shouldn't have saved me at the cost of your own life,” Arthur told him, his anger fading.
“We’ve been over this. Your life is worth more than mine. You're the king. I'm just a servant,” Merlin said matter of factly.
Arthur felt sick to his stomach. “Do you honestly believe that? You really think that's all you are?”
Merlin looked confused.
That look was all Arthur needed to have his answer. “You're more than just a servant. You always have been. You're my best friend.”
“And you're mine. But that doesn't change the fact that you're more valuable to the kingdom,” Merlin tried.
“Damn the kingdom!” Arthur shouted, taking Merlin by surprise. “I wouldn't be able to function without you. Remember how much of a- a- a prat I was before you came along?”
“You talk as if you aren't anymore,” Merlin teased, and Arthur would have grinned if the conversation weren’t so serious.
“Don't make this into a joke. You need to listen to me for once.”
Merlin nodded, subdued.
“Okay.” Arthur took a deep breath. “Without you, I'm afraid I'd become my father. Turned insane by his loss. Not fair, not just, only desperate for revenge.”
“Arthur, now you need to listen to me,” Merlin responded, shaking his head. “You are a better man, and a better king, than he ever was.”
“Only because of you,” Arthur told him.
Merlin felt like objecting. Felt like telling Arthur that he had always been good, Merlin had just helped him to show it a bit more. Wanted to argue that even before he had come, Arthur had tried to make sure the kingdom was a fair one. Instead he just smiled. “I’d better stick around, then.”
Arthur smiled too. “Yeah.”