Almost as soon as the thought to use sorcery entered Merlin's mind, he could feel magic welling up beneath his skin (er, scales). It was vibrant, almost hot in its pure power, but somehow manageable. He felt strong. There were no words. There weren't even tangible thoughts. Where his magic had once been laced in his blood, it was now an extension of himself, like an arm or a leg. He didn't have to think about the gusts of wind which buffeted Morgana's wings, or the birds he conjured from clouds whose pecking beaks were nowhere near as soft on the white dragon's scales.
Merlin made to bank in the air, wanting to watch his handiwork, but he was still a novice to flight and fell a few terrifying yards through the air before he caught himself. Morgana had forgotten him completely. She was hissing, snapping her jaws at the puffy falcons which had formed three separate mobs—one about her head, and one about each wing. The first group of birds were acting largely as a distraction, scrabbling for her eyes and tearing at her face, but the other two were doing something far more deadly. Formed from clouds, the falcons had the same amount of condensation in their cores—and the same propensity to freeze. They alighted on the edges of the dragons wings and seemed to ooze together, feather joining with feather until they had created twin encasements of ice.
The white dragon plummeted in a dizzying spiral, followed by the remaining cloud-hawks like ghostly echoes of her scales. Merlin watched Morgana's plight, hovering in the air, his heart racing and a sick feeling in his stomach.
Merlin, you know what you have to do.
"She'll be back," he said quietly, morosely. "She'll be back and who knows how many people she'll kill. She'll destroy Camelot, Kilgharrah."
Morgana must be destroyed, yes, but not now. Not like this. Aithusa is the last of her kind, young warlock, and she does not deserve to die for the actions of her mistress. You cannot kill the last true dragon for the sake of Morgana.
Merlin hesitated a moment longer but in a few seconds Morgana would make contact with the treetops, and it would be too late. He dove after her.
The wind whistled around his body but it found no harsh edges to buffet against. His wings had all but collapsed, folded along his back, and to a spectator he might have looked like a black ribbon being pulled towards the earth. Merlin urged himself to go faster, conjuring a wind to propel him after Morgana's form as the wave of green grew closer and closer. In the back of his mind he wondered if he himself would be able to pull up in time. He'd never gone so fast in his life and he was a poor flyer anyways, and it was exhilarating and frightening but he had the time to dwell on neither.
He was coming up on the dragoness and he couldn't think, couldn't imagine anything but the feeling of the trees as they splintered through his bones and so for the second time he parted his lips and doused Morgana in flames.
She screamed and it was not a sound of pain— her scales made her immune to the heat. It was a sound of fear, and Merlin inwardly flinched against it. There was no doubt in his mind that Morgana was remembering the last time she had seen fire so close.
The ice encasing her wings melted within seconds but it felt like an eternity before she was able to move them and Merlin was certain he was too late, he'd taken too long and she was going to crash down to the forest floor, but suddenly she shot upwards like a bullet, slamming into him.
It had been a glancing blow, but Merlin had been flying so fast that the impact sent him tumbling out of control. Morgana flew out of sight without so much as a backwards glance as the black dragon tore through the very tops of the trees.
"My lord?" Someone was shaking him, and it was gentle but the motion hurt like hell and one of his ribs was definitely broken.
"I'm fine," Arthur tried to wave whoever it was away and they pulled him to his feet. He groaned. "What happened?"
"The dragons took off that way," Blaise said, and his voice had the quality of a man half-asleep. "Merlin was leading her away, but I lost sight of them through the trees."
"We've got to go after him," Arthur reached for his sword, lying in the dirt next to where he'd fallen, and sucked in his breath as his midsection seemed to catch fire.
"And how will that help Merlin?" Another knight asked, but suddenly Percival spoke. He was at the very far edge of the clearing, and as Blaise and Arthur turned, he pulled himself upright on a tree branch.
"I can see them! They're about a league north of us, maybe less, and…" he faltered.
"What?" Arthur asked impatiently, starting towards Percival.
"They're falling," the knight whispered, his face pale. Ignoring Blaise's attempts at ministration, Arthur untied his horse and swung himself onto the saddle. He half-expected Percival to protest, but the man was already on his own steed and galloping northwards.
The group rode at a breakneck pace and within minutes they could hear roaring. Through the gaps in the trees Arthur could see two shapes ahead of them—one far lower and far larger. Morgana. There was something wrong; her wings didn't seem to be working and she thrashed with a panicked fervor, and Merlin was darting after her. Suddenly there was fire shooting from the black dragon's maw, and tongues of it shot back towards Merlin, but when he seemed unfazed the king realized the fire was harmless. A moment passed and Morgana's wings seemed to be changing shape, and Arthur understood that his friend was saving the other dragon.
He was confused, but the confusion changed within moments to rage and fear. Her wings defrosted, Morgana careened into Merlin in her path to escape, and he was thrown to the side, his previous momentum now sending him through the top of the forest with blinding speed. There was a terrible chorus of snapping, like miniature explosions, as he rent a path through the trees. It was a blur of black to the knights but he passed within a few yards of their party before finally skidding to a stop. Compared to the awful sound of his descent, the quiet that followed was deathly.