Draco Dormiens Nunquam Titillandus. Never tickle a sleeping dragon. The Hogwarts School of Witchcraft and Wizardry motto. A message to act with caution. A message that the worm known as Delores Umbridge had clearly missed the obvious warnings of and, figuratively speaking, poked the dragon in the eye with a glowing red hot metal rod. And that dragon, or rather Demi-Dragon Goddess, was angry. No. Furious.
Stating that pretty much everyone in the Great Hall felt nothing but fear and dread as the doors were flung open and the murderous aura flooded in with the arrival of the source of the aura. Blake Ouroboros, who wore an expression of pure unadulterated rage and appeared to be in the process of transforming into something reptilian, or rather draconic. Silvery grey eyes with slitted pupils completely locked on the worm in pink, who clearly lacked any survival instincts as she was basically oblivious to the malevolent glare aimed at her.
"You." Exclaimed Blake while pointing a finger that resembled the digit of a beast more than the digit of a human, at the worm in a much deeper tone than normal.
"What, half-breed!?" Replied the worm.
"You hurt my daughter, worm. Tonight, you die. Any last words?" It should be known that Blake was turning more and more draconic as she slowly approached the staff table. Completely uncaring of the sounds of her clothes slowly ripping, tearing and shredding as her form changed.
By the time the furious Demi-Dragon Goddess reached the center of the Great Hall, all semblance of Blake Ouroboros' human form (and her clothes) was gone and in its place was the form of a massive black Dragon. It's horns, spines and talons weren't composed of keratin but some kind of dark purple crystal that glowed ominously. The crystalline talons digging deep in the cold stone floor with a sound akin to metal scraping against metal (A/N: Blake's dragon form is based on Fatalis).
"You're… you're… you're-" whatever the worm was unceremoniously cut short by a dark purple ball of energy striking her body and causing her to disintegrate.
"Time's up, worm. No one will miss you." Muttered Blake before being engulfed in a blindingly bright pale purple light and vanishing from the Great Hall.