This girl was certifiably insane!
That single thought consumed Voldemort's remnant soul.
The more the Fiendfyre grew, the harder it became to control! Especially this Fiendfyre, so specifically "cultivated" that it had reached a level only a wizard of his caliber could manage! Consequently, the Fiendfyre had become powerful enough to threaten him. After all, a flame that could use anything as fuel and continuously grow was a remarkable skill for punching above one's weight.
But Cassandra simply couldn't control it! This meant the Fiendfyre would attack friend and foe alike! Everyone was a target, including Cassandra. This unlucky girl was gambling with her life!
Why?!
Voldemort's remnant soul couldn't fathom it. What was so vital, so desperate that she'd risk everything? Couldn't they just talk? Couldn't he just surrender? If she died, he'd go down with her!
His mind spiraled. What had he done to offend Cassandra so deeply that she would want to die with him?
If he dared use Legilimency, though, he'd realize Cassandra wasn't afraid of the Fiendfyre going out of control. When it came to understanding and controlling Fiendfyre, Tom Riddle was unparalleled. Cassandra's alchemically enhanced robes were imbued with defenses specifically designed by Tom based on his intimate knowledge of Fiendfyre's nature. Without exaggeration, these were the most potent Fiendfyre defenses of any alchemical artifact.
Unless a wizard of Lanlock's caliber cast it, the Fiendfyre couldn't instantly breach the robes' protections! And the time the artifacts bought her was enough for Cassandra to escape the flames.
Therefore, the only one who would burn to death was him! Voldemort's remnant soul!
He dared not use Legilimency on Cassandra, or even Harry and the others, fearing Tom had left some nasty surprises for him. Otherwise, with Legilimency's ability to foresee the future, he would have already subdued these brats.
But it was too late for that now. He needed to find a way out. The Fiendfyre, having grown to this magnitude, was too much for him alone. He knew a low-level version of "End of Curses" he could cast, but it only worked on weaker Fiendfyre. This Fiendfyre, comparable to a legendary wizard's power, required the full version of End of Curses cast by another to defeat it.
Even worse, his Apparition ability had been stripped away, making escape impossible. The Fiendfyre could burn everything; even the black mist he conjured with the Flight Charm would ignite.
But that wasn't the worst part!
What tormented him most was that he had to save that brat! Otherwise, even if he escaped the Fiendfyre, he wouldn't survive if she died!
But saving Cassandra, protecting her from the flames—running back and forth like that, he might actually die here!
Voldemort's remnant soul nearly wept. Grandma, if you want to hit me, just say so! I'll stand still and let you hit me, okay? Can't we just not play with fire? This is dangerous!
Though he wanted to cry, he knew now wasn't the time. He had to hurry!
He dropped the barrier constantly eroded by the Fiendfyre, leaving only a single layer protecting his body. Voldemort's remnant soul cast the Flight Charm again, flying rapidly toward Cassandra's last known location!
The looming Fiendfyre made his heart pound. He was terrified he'd be too slow to save the girl, and even more terrified he'd be burned alive.
But when he arrived, he was dumbfounded. "Where is she?!"
Gone! Everything was gone!
The young lady is dead! I'm doomed too!
Voldemort's remnant soul froze, instinctively dispelling the encroaching Fiendfyre, though it quickly returned.
"Then let's all die together—!"
Voldemort's remnant soul dove downwards at breakneck speed! He would kill all of Harry Potter's gang! He wasn't going to survive anyway! Why care about anything else!
Die together!!!
...
Legendary wizards, it turned out, weren't so easy to kill.
Though Voldemort's remnant soul was more disheveled than ever, he showed no signs of dying, not even serious injury. He was like a cockroach among cockroaches, incredibly hard to kill.
"Die, all of you... wait, what?"
Voldemort's remnant soul looked down to see Cassandra chatting unharmed with another witch below.
"..."
Fine, he couldn't kill them again. He had finally decided to die with them, and now he was being told he didn't have to? But he couldn't kill them either?
It was generally a good thing, but Voldemort's remnant soul felt even more uncomfortable.
Despite his discomfort, he still wanted to live. However, he truly didn't want to fight anymore. He didn't want to deal with these guys anymore. Let them beat him up if they wanted; he just wanted to break free of that damned shoddy confinement!
And get away from that crazy brat!
He'd stay far away from her in the future! Otherwise, given what happened just now, even he could be killed if it happened a couple more times!
...
Below, on the ruins.
Seeing Voldemort's remnant soul had survived, Cassandra and the others were incredulous, especially Cassandra, whose expression was far from pleasant. She had used the strongest magic she could muster, after using numerous Weather Charms to fuel the Fiendfyre.
And yet… "Even so, we still can't defeat him?"
"This guy… he's really strong."
Hermione also realized they wouldn't defeat Voldemort's remnant soul anytime soon. Barring unforeseen circumstances, they simply couldn't defeat him!
The gap between an ordinary wizard and a legendary wizard was too vast! Even the Socket Boy, powerful enough to be among elite Aurors as an adult, only truly became a Legendary Wizard in middle age.
Dumbledore and his contemporaries were similar, even later than the Socket Boy.
In the entire history of magic, probably only a freak like Tom Cruise could surpass the level of Legendary Wizard by adulthood… no, Tom Cruise had already surpassed the level of Legendary Wizard by adulthood, just not becoming the God of Magic.
In Grindelwald's words, this kid was probably already a Legendary Wizard by fifth year, and that's a conservative estimate!
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