A gigantic, misshapen hand crashed through the ceiling, shattering wooden beams and stone bricks with such ease that the castle might as well have been built of cards. Several teachers raised their wands, halting the hand in its tracks and keeping the ceiling from collapsing upon everyone's heads, but the rest of the creature to which the hand belonged soon came crashing through the castle's outer walls, sending bricks skittering across the Entrance Hall and raising a smokescreen of powdered mortar and stone.
"Neville, Astoria!" Oleandra shouted, spotting their gleaming blades through the swirling veil of dust. "Go for the legs!"
Magic was of little use against Giants, let alone armoured ones, so it would fall to them to bring the monster down with cold steel. Forged of Goblin Silver, the Sword of Gryffindor could cleave through the Giants' metal armour and pierce their tough hides, and Arondight and Excalibur, wrought of Fairy-forged cold iron, could do the same.
Astoria turned into a scarlet blur as she weaved through students running for cover, dodging falling stones and flashes of magical light. She slashed at a gap in the Giant's armoured sandals, and her blade bit deep, severing its ankle's tough tendons as easily as a hot knife through butter. The Giant roared in pain and stumbled, and as it turned, Astoria wrenched her sword free from its ankle in a spray of blood before it could be torn from her hands.
The Giant swiped at her with its mighty hand, forcing her to jump backwards. Taking advantage of its distraction, Oleandra flew up to its face and swung Excalibur, unleashing a wave of golden sword light into its eyes, while Neville darted between its legs and severed the tendons in its other ankle. Blinded and unable to stand, the Giant toppled backwards into one of its companions, accidentally striking it with its club.
Enraged at this perceived affront, the second Giant began attacking its companion, squashing underfoot the first line of golden-cloaked Heliopaths rushing into the castle after them in the ensuing struggle.
The air was soon filled with streaks of multicoloured light, and for Oleandra, the battle became a blur of flashing sword light and magical bolts. She swung her sword ceaselessly, swatting away bolts of magic and cutting at anything that came too close, and when her arms grew tired, she simply kept on swinging, until a lull in the fighting finally came, as the Heliopaths and the Death Eaters seemingly paused their assault on the castle…
A hunting horn resounded, and the Giants and Trolls turned to the north…
"Centaurs!" someone exclaimed.
The dust quickly settled as the Death Eaters stopped hurling Exploding Curses at the castle, and Oleandra peered into the distance. Indeed, it seemed as though the cavalry had arrived. The Centaurs crashed into Voldemort's army's rear, sending the hooded Wizards and Witches scrambling out of the way of their hooves as they thundered through them, loosing arrows from their bows at anyone they did not like the look of, and by the time the Death Eaters had finally regrouped and mounted a proper defence, they were already cantering back into the relative safety of the Forbidden Forest.
Taking advantage of the lull in the fighting, Oleandra downed a Strengthening Solution from her bottomless pouch, wincing as a burning sensation spread through her limbs and her muscles rapidly recovered. She was still exhausted, but at least this would lighten the burden of raising her sword again.
"NO!"
A terrible scream of pure fury suddenly rang out from the enemy's side.
"It's the Insigil of Lindorm!" Oleandra shouted, brandishing her sword in the air as she spotted a long, silvery, dragonlike creature veering around the castle's side and crashing into the side of Voldemort's army. "Tracey's done it!"
It had been two years since Oleandra had unleashed the Dragon's Insigil against Voldemort at the conclusion of the Battle in the Department of Mysteries, forcing him to flee for his life. Many in the Wizarding community had already read Auror accounts of the spell's awe-inspiring might in The Daily Prophet, but for most, it was the first time they had seen it in person…
The Trolls were the first to suffer the Lindworm's wrath. Despite being merely a phantom of the real monster, the serpentine apparition made short work of them, its flashing fangs and claws tearing through them as it slithered through their ranks. The Giants were next on the menu, and as they turned to meet the ghostly Dragon, they soon discovered that their weapons were completely ineffective against it, while their armour could not withstand its razor-like teeth.
A serpent of flame suddenly swept into the Entrance Hall, barely halted by the teachers' concerted effort. Entranced by the Lindworm's might, the defenders had almost forgotten about Voldemort and his goons!
"Retreat!"
Surprisingly, the call to retreat came from the mightiest duellist amongst then, Professor Lockhart. Somehow, he had already managed to worm himself all the way to the back. He already had a foot in the North Hall, beckoning for everyone to follow him.
"Retreat!" roared Shacklebolt, seeing the wisdom in Professor Lockhart's judgment.
The Bell Tower had been reduced to rubble, so there was simply nowhere to take cover from Lord Voldemort's unstoppable Killing Curses.
Oleandra floated up into the air, lazily weaving to and fro to avoid beams of crimson light from the incoming Death Eaters. Voldemort was flying low towards them, leading the charge— though not by bravery, but because he feared the Lindorm more than any of his supporters ever could.
"Harry, what are you doing!?" Oleandra shouted as he advanced fearlessly towards Voldemort, even as everyone around him fled. "Get back, you'll get yourself killed!"
"Take me, but spare the others," he said loudly but clearly, not even bothering to raise his wand. "You promised, didn't you?"
Voldemort sneered, levelling his wand at him. Oleandra swooped down as fast as she could to push him out of the way…
"Avada Kedavra!"
…but she was too slow.
There was a bright flash of emerald light as the beam struck Harry in the chest, and he toppled over backwards…
"Harry!" Oleandra heard Hermione and Ron scream.
…and then everything turned to white.