The plan to secure Nagini was an operation of such immense risk and required such a high degree of stealth that it could not involve the Order of the Phoenix. It could not involve Aurors. It was a mission for a team of three: a spy who could walk through the front door, and two ghosts who can slip through the shadows.
Snape, his loyalty now absolute and his mind shielded by a lifetime of Occlumency, was the key. Over the next week, he fed Ariana meticulous details about the Lestrange estate: the warding schemes, the patrol schedules of the Death Eaters, and, most importantly, Voldemort's own habits. "He keeps the snake with him at all times," Snape reported during a secret meeting, his voice a low whisper. "But at night, during the three hours he enters a state of regenerative trance to maintain his new body, the snake is allowed to roam the manor's sealed gardens to hunt."
"Three hours," Ariana mused. "The window is sufficient."
The plan was set for the next new moon, when the darkness would be absolute. The mission was not an assault; it was an extraction.
On the chosen night, Snape attended a meeting of the Death Eater inner circle at the manor. While he was inside, providing a perfect alibi and a subtle magical distraction by engaging a few guards in a pointless, lengthy debate over potion ingredients, Ariana made her move.
She did not Apparate to the gates. That would have triggered the wards. Instead, she Apparated to a point a mile away and approached through the dark, gnarled woods. She was a shadow among shadows, her presence completely masked by a powerful Disillusionment Charm woven with her own unique, silent magic. Midnight immediately appeared out of her shadow.
They reached the perimeter of the estate. The wards were ancient and vicious, designed to repel any magical being with hostile intent. But Ariana's intent was not hostile. It was, in its own way, restorative. She was not there to attack; she was there to heal. Also, the fact that Ariana was technically the owner of the Lestrange properties meant that the magical wards did recognize her magic as the owners. With a soft, silent push of her will, she slipped through them like a ghost passing through a wall.
She found the gardens. They were overgrown and filled with poisonous, dark-magic-infused plants. And slithering through the undergrowth, its iridescent scales a faint shimmer in the oppressive darkness, was Nagini.
Ariana did not approach directly. Instead Midnight was used to bring out Nagini out of the closure. The magic of one being will of course identify another. And Midnight was going to be the bait.
Nagini, hunting a small, unfortunate garden gnome, froze. Her great head rose, her forked tongue flicking out, tasting the strange, magical presence in the air. Curiosity warred with her ingrained suspicion.
Ariana waited patiently, her presence completely concealed. Finally, drawn by an instinct she didn't understand, Nagini slithered towards the source of the feeling, towards a quiet, shadowed corner of the garden where a weeping willow trailed its branches to the ground.
As the great snake passed behind the curtain of leaves, Ariana and Midnight acted.
It was not a battle. It was a perfect, silent takedown. A pounce from Midnight to startle the snake and a powerful, non-verbal sleeping spell, and the air already infused with the same core-recession properties of her anesthetic potion, struck the snake. Nagini's magical core was instantly persuaded into a state of deep, peaceful dormancy. Her great body went limp, slumping to the ground in a deep, dreamless sleep.
Working quickly, Ariana levitated the massive, unconscious serpent. With her other hand, she pulled out a small, enchanted object Sirius had given her—a shrunken, feather-light trunk. With a tap of her wand, it expanded to its full size. She gently placed the sleeping Nagini inside, cast a series of powerful stasis and silencing charms upon the trunk, and then shrank it once more. Midnight back to her side.
They slipped back through the wards as silently as they had entered. The entire operation, from infiltration to extraction, had taken less than fifteen minutes. No alarms had been raised. No one was the wiser.
Back in the shielded silence of her London flat, the real work began.
She placed the sleeping Nagini in a large, magically reinforced containment circle in her laboratory. Midnight already back to her corner. First, she had to deal with the Horcrux. The procedure was now second nature to her. The anesthetic potion, the Parseltongue command, the Exsilium Animae, the Claustrum Aeternum. The screaming fragment of Tom Riddle's soul was ripped from the serpent and sealed within its fifth obsidian prison. The primary infection was removed.
Now came the far more delicate and unknown part: treating the Maledictus curse itself.
She did not wake Nagini. She kept her in the magically induced state of slumber. Her theory was that the curse was a parasite that fed on the host's despair and active magic. In a state of prolonged, peaceful dormancy, the curse would be starved.
For days, she worked. She applied complex healing charms, not to attack the curse, but to slowly, painstakingly repair the tiny, hereditary fractures in Nagini's own magical core. She was not just killing the parasite; she was healing the host, strengthening it from the inside out, making it an inhospitable environment for the curse to thrive.
After a week of this intensive, round-the-clock treatment, she sensed a change. The dark, chaotic energy of the curse within Nagini was weakening, fading, like a dying ember. The procedure similar to Astoria was performed next to remove the curse from her body.
Then came the final, most dangerous step. Reversing a physical transformation that had been permanent for decades. She gathered her full power. She reached out with her will and began to rewrite Nagini's physical and magical code, persuading it to remember its original form, the human form it had not known for so long. It was a form of Legilimency similar to what Ariana had used on the Longbottoms, an active willpower guiding the magic.
A brilliant, silvery-white light enveloped the great serpent. Its form began to shimmer, to shift. The scales receded, the massive body shrinking and contorting. It was an agonizing, elemental transfiguration, a battle for form and identity on a cellular level.
When the light faded, there was no snake. Lying peacefully asleep in the center of the circle was a woman. She was older, her dark hair streaked with grey, her face lined with the memory of a long and difficult life. But she was human.
Ariana waited. She gently administered a final potion, one to ease the transition and awaken the mind.
The woman's eyes fluttered open. They were dark, intelligent, and, for the first time in a very long time, completely sane. She looked at her hands, her human hands, and then at Ariana, who stood watching her with a calm, gentle expression.
"Who…?" the woman whispered, her voice a hoarse, unused sound. "Where am I?"
"My name is Ariana," she replied softly. "You have been unwell for a very long time. But you are safe now." She paused, then added the name that was both a memory and a promise. "Nagini."
The woman stared at her, and in the depths of her dark eyes, a flicker of an ancient memory, of a circus, of a boy named Credence, of a life before the curse had taken everything, began to stir. The long, lonely nightmare was finally over.