At first, Arthur thought the sound was another patient.
As soon as they'd made it back to Camelot he and Merlin had been sent to Gaius's chambers at the behest of the other knights (namely, Percival), but as they neared the door a pained, hacking cough stopped the two in their tracks. Merlin was the first to stir, walking through the door like as if he were asleep.
"Everything alright?" Gaius was hunched over the table, and as Arthur spoke the physician turned. His skin was pale, deathly so, but his eyes were unnervingly bright.
"It's just a cold," he waved a hand, trying to speak airily, but his face turned red in an effort to stem another bought of coughing. Merlin almost ran to him, leading him to a bench. "I shouldn't have been out in the rain, that's all. Sometimes I forget how… old I've gotten."
"Don't say that," Merlin frowned and sat next to Gaius. He looked upset.
"It was bound to happen eventually, my boy. Age catches up with the best of us."
"What are your symptoms?" Merlin was standing again, rifling through the carefully labelled jars with such speed that Arthur feared he'd break something. He began laying a few out on the table—angelica, horehound, cress. "Do you have a headache? Fever? Nausea? Aches? I can make you a tea. Or a—"
"Merlin, truly, it's just a simple cough," Gaius protested, but Arthur sensed he was trying not to worry his ward. There was a quiet edge to his voice that it scared the king more than the soft rattling he'd noticed in the physician's chest.
"I don't think so," the sorcerer said resolutely, giving Gaius his best caretaker's glare as he held a hand out to feel the man's forehead. "Gods, you're burning up. I'll add some laurel."
"Do you know what it is?" Arthur spoke quietly so Merlin wouldn't hear. Gaius paused, sighing deeply.
"I'm not entirely certain, sire, but it is familiar. And I don't think any amount of tea is going to help me."
Aithusa was still flying when an unfamiliar voice sounded in her mind.
Soon, little one. Tell your mistress she is not alone in her noble quest.
The dragon felt power emanating from the speaker, but also a strange absent quality. Whoever it was seemed like a specter—not quite here, not quite there. See-through.
Emrys can only straddle the line between his kind and yours for so long, my pet. Soon he will have to choose. And to save his precious king, he will always choose the same. It's almost a shame to waste such a pretty face.
Morgana picked up the scale then, sensing something was amiss.
"Aithusa? Where have you—"
The hermit queen, the voice said, and there was a smirk in the words. Tell me, does the blacksmith bitch still sit on your throne?
"Who are you?" Morgana jerked upright, her eyes wide and searching in the dark.
If we met, darling, it was only briefly, and more's the pity. We would have made a great team. We'll make a great team yet.
"Identify yourself, coward."
Coward?
"Why else would you hide in the shadows? Are you scared?"
Scared? There was the ghost of a laugh. It is you who should be scared of me. The Triple Goddess may have abandoned you, my love, but She never forgot me.
"I'm not abandoned. I—"
You're sitting in a hovel, blind and afraid.
"And you?" Morgana spat.
I'm getting stronger. She imagined the sound of a shrug. In her infinite mercy the Goddess wakened me to do Her holy work. The sorcerer must be destroyed.
"Who are you?"
I preceded you and your late sister in both life and power. I am a High Priestess, and I am the woman who kills Emrys.
"And you want to work together?"
I am still weak, Morgana, more weak even than you. My hold on this world is tenuous. It is getting stronger, but it will be some time yet before I can walk among men.
"What do you need me to do?"
Every moment Emrys takes the form of a dragon heightens the chance that he'll be unable to return to his human self. He will forget his name, and even his powers- which if I'm not mistaken, is how he bested you.
"So you need me to coax him out?"
He will do anything for Camelot, and above all, for Arthur. I trust you can figure out the rest. But Morgana?
"What?"
Save the final blow for me.
Morgana and Aithusa both could sense the presence disappearing, receding back to wherever it came from, and the sorceress relaxed into her pillows. This stranger could be useful. A single High Priestess was powerful, but two…
She didn't know how she would go about luring Merlin to the skies, or even the name of the woman she was considering working alongside, but she did know one thing.
The only one who would strike the blow ending Merlin's miserable life would be her.