Courtroom 10 was a large, octagonal chamber, each corner supported by black marble columns. The entrance through which Oleandra and Mai had just arrived lay on the same level as the floor where the Muggle-born cowered before the Dementors, directly opposite the raised bench where Yaxley sat. The floor was ringed on seven sides by elevated stands, where the Wizengamot would usually sit in judgment, though the seats stood empty now.
Evidently, there was no justice to be found here.
As the dark-robed entities glided towards them, over the stands and the cowering Muggle-born, Oleandra began to wonder whether You-Know-Who hadn't emptied Azkaban of its Dementors entirely. If more of them were to appear, she had no idea how she was supposed to keep her identity a secret.
"Expecto—"
A solitary ray of red light streaked across the room and struck Mai in the side of the head. Her head jerked to the side, and she stumbled back a few feet, shaking her head to clear the dizziness.
"Mai!" shouted Oleandra in alarm.
There was no cause for immediate worry; Mai was Fae, just as she was, and could not be knocked unconscious through magical means. Reflexively, Oleandra lowered her wand, fingers curling into an 'OK' hand sign, and pointed her hand towards the source of the attack.
"Thu—"
Oleandra closed her hand into a fist and gritted her teeth. How could she have forgotten, even for a fraction of a second, that the activation of runic magic was delayed or simply failed outright when underground, where the light of the stars couldn't reach her? The Dementor's dread aura was making it difficult to think rationally…
Eyes flitting left and right, Oleandra realised that guards had been posted in each corner of the room. Judging by the glint of their golden capes and radiant sun-shaped badges on their breasts, she surmised they were the so-called Heliopaths that You-Know-Who had been so interested in acquiring, along with the prophecy orb two years ago.
"Take care, Mai!" Oleandra shouted as she took cover from a volley of Stunners by diving behind a pillar. "These aren't your run-of-the-mill Death Eater!"
It would be her first time encountering the Department of Mysteries' Special Anti-Muggle Task Force on the field of battle, so she wasn't entirely certain what to expect of them. Oleandra poked her head out from behind the pillar, only to pull it back almost immediately, receiving a faceful of stone fragments for her trouble, as more Stunners exploded against the pillar.
"Behind you!" Mai shouted. "Protego!"
Standing out in the open, even behind the pillars at the entrance, they were like sitting ducks. To make matters worse, the enemy not only surrounded them but also held the high ground, and judging by the chill building up on the stone columns' surface, they were about to be flushed from their cover by the Dementors.
"Patronus Charm," said Oleandra nervously. "Any day, now."
Mai squeezed her eyes shut, her brow knitted in concentration.
"You're asking a lot out of me, big sister," she muttered. "In case you've forgotten, I'm only twelve."
A child's spellcasting capabilities are limited by their undeveloped magical circuits.
While intelligence, imagination, and talent dictate how easily a wizard can learn magic and how well they can develop their innate abilities, magical potential defines their limits. Just as Ron could never surpass Harry or Hermione, neither Harry nor Hermione could hope to match a once-in-a-century wizard like Dumbledore, whose sheer magical genius and extraordinary magic channelling capacity were unparalleled.
But talent is not all important.
Even had her magic never been sealed at birth, Oleandra would have remained a mediocre Witch at best, yet she had still become one of the most skilful duellists in the British Isles, despite Merlin handicapping her starting abilities. Her success was entirely due to her mastering the magic of runes, which perfectly suited her current, weakened incarnation!
It just goes to show that, in a world of magic and wizards, the very notion of limits is entirely arbitrary; when it comes to power, it is merely a question of how hard one is willing to train, how much one is willing to sacrifice, and which taboos one is prepared to break!
Oleandra was not willing to sacrifice the secret of her true identity, but not at the cost of her life.
"Expecto Patronum!" Oleandra roared, stepping out from behind her pillar and pointing her wand at the ground.
At once, the octagonal floor was flooded with waves of dancing, silvery light. All sorts of fish and waterfowl, filled with Oleandra's most cherished memories perfectly recorded in her Fairy's soul, burst out of the white lake's surface as it expanded, chasing the dread Dementors out of her domain and Banishing them back whence they had come.
"Vee?" Mai mouthed, eyes wide as saucers.
Where Nymphadora Tonks had once stood now stood a tall, glamorous woman in nearly translucent blue robes that shimmered like morning sunlight dancing on a lake's surface, an azure feathered cloak floating about her shoulders.
Inadvertently, Oleandra's stolen Metamorphmagus power had run wild with her emotions, transforming her into her staunchest mental pillar: Viviane. The Muggle-Born huddled at the base of Yaxley's podium, no longer transfixed by the Dementor's oppressive aura, stared at Oleandra's ethereal form in wonder.
"What are you lot still standing around for?" Oleandra yelled at them. "Get out of here if you haven't a wand— fight if you've got one!"
Chaos erupted as those whose wands hadn't been confiscated yet drew them and fired wildly into the stands. Taking advantage of the confusion, Oleandra and Mai rushed into the stands, circling around the Heliopaths firing at their fellow Muggle-Born below, Stunning them one by one until none remained.
And at last, there was only one enemy left.
Leaning against his podium and nursing his side, his black robes darkened with his own blood where Oleandra's Reductor Curse had grazed him, Yaxley looked up to find her holding him at wandpoint.
"Kill him," said Mai shortly, as she walked up to them. "He knows who you really are. I can see it in his eyes."
"Please spare me," Yaxley croaked. "I won't tell anyone, I swear."
If she let him live, she had no doubt that, even if he kept his promise, the truth would sooner or later be extracted from him, memories wiped or not. There was only one way to ensure he didn't speak.
"We can't take him back either, in case that's what you were thinking," Mai whispered softly in Oleandra's ear. "In case you've forgotten, we're at war. Each person he kills from now on will be on your conscience."
Oleandra's wand trembled.
While she had slaughtered many— from Dusk Elves and Death Eaters to Druids— she had never taken another's life in cold blood. Never had a more vile, undeserving character presented himself for the killing before Oleandra, and yet she still hesitated, for this was a line that could not be uncrossed.
"Do it," spat Mai.
She was right.
Yaxley could not be left alive.
"Better not to offer than to slay too many," Oleandra said, drawing a sharp breath. "Avada Kedavra."
There was flash of blue light, and the Death Eater's head drooped, his eyes glassy and lifeless.