Ivy Doom was a smart person.
Or rather, he was someone who thought of himself as smart. And, until now, no one had ever argued that he didn't deserve that label.
Therefore, fighting with Dumbledore was something he had planned from the very beginning.
The reason was simple: to destroy the evidence.
As a master of the Dark Arts, especially the infamous "Avada Ke-Doom" curse, his ebony wand had taken the lives of more than one person.
And facing the greatest wizard of the 20th century, keeping evidence was an incredibly unwise choice.
With just a small "Reversal Charm," Ivy would be exposed by the magic of his wand. While he was fairly certain that the magic he used most often was "Reveal True Form," it didn't mean that Dumbledore wouldn't notice the "Unforgivable Curses" hidden within.
Although Ivy believed every person he had killed deserved it, he certainly didn't want to end up in Azkaban under the so-called "Hogwarts Extension School" interrogation.
Therefore, destroying his wand using ancient magic seemed like the best solution.
An even better solution, however, was to get Dumbledore involved in the process.
Thus, when Ivy heard Dumbledore introduce himself, the first spell he cast was "Protego," showing that he was a duel-focused wizard who valued his safety, rather than a reckless gambler.
Then came "Expulso," a spell to keep a safe distance, still not an offensive spell, lowering his aggressiveness while subtly lowering Dumbledore's guard.
After Dumbledore introduced Snape as the Head of Slytherin, Ivy cast his first offensive spell—"Expelliarmus," not deadly, but enough to show his intent.
Next, he revealed his ultimate move: the ancient magic thunder strike, dueling with Dumbledore, and using ancient magic to destroy his wand.
This demonstrated both the power of ancient magic and its instability.
Finally, after pulling out a second wand and with Snape's timely help, Ivy "lost his ability to resist" and surrendered, raising his hands in a mock salute, giving Dumbledore and Snape the impression of a "Slytherin who values his life."
At this point, the entire design of the duel was complete, and now it was time for the conversation. What Ivy could rely on, besides his ability to adapt, was a careful mouth.
"Feyrfin silver... or maybe some ingredients I don't know about..." Snape said with a stern face, examining Ivy 's silver-glinting wand under his nose. He then handed it to Dumbledore before turning back to Ivy, still dragging his long robe. "A little unshaven wizard... dared to attack two grown wizards... and used magic he didn't even fully understand… If you hadn't raised your hand fast enough, I would have thought you were a Gryffindor fool."
Ivy scoffed, not bothering to respond, but his expression clearly said, "You've got the power, you win."
"...Exquisite craftsmanship!" Dumbledore said, peering through his half-moon glasses, still praising the silver-glinting wand. "Alright, maybe now you're willing to have a chat with us? This one..."
Ivy shrugged, looking utterly reluctant as he introduced himself: "Ivy. Ivy Doom."
"Very well, it seems we've reached some understanding, Mr. Doom." Dumbledore tried waving the wand that had been taken from Ivy 's hand, but only a little spark fizzled weakly at the tip of the wand, and then it completely stopped. "You look like a Hogwarts student. So why attack us?"
"Not going to ask about ancient magic?" Ivy shrugged. "Well, that doesn't matter." He then shot a question back, "Have you ever seen me at Hogwarts? Of course not. Because I've never seen you either."
"Oh..." Dumbledore nodded, seemingly agreeing with this.
"I'm a fifth-year student at Hogwarts, though I'm a transfer, my grades are top in all subjects, all the teachers like me, and according to Professor Black—uh, I mean Headmaster Black, I'll be elected as the Prefect next year!" Ivy said with a proud look on his face before glancing at Dumbledore. "But I've never seen you at Hogwarts, not even in a portrait!" He then turned to Snape. "And you too!"
"So, you absolutely can't be the headmaster or professors of Hogwarts. If we're both telling the truth, then there's only one possibility: one of us traveled through time!" Ivy snorted in satisfaction with his deduction. "And we all know the Ministry of Magic strictly monitors Time Turners. They've even been considering drafting stricter laws to regulate their use. I suspect it will take them at least twenty years to write it into law."
The regulations on Time Turners were issued by the Ministry of Magic in 1899, and Ivy had read discussions about this law in the Prophet Daily during his schooling. Although he didn't know what had happened afterward, Time Turners were considered dangerous and tightly controlled items.
This was Ivy's version of improvisation.
"Speaking of the Black family headmaster of Hogwarts, the only one I can think of is..." Snape squinted at Ivy's face, as if trying to find some flaw, but Ivy's disguise was flawless—there were no cracks.
"Phineas Black, who else could it be? He was one of Hogwarts' great headmasters, and everyone says so." Ivy looked around and then lowered his voice slightly, "What I mean is, Headmaster Black was also a great wizard. Absolutely no other implications, I promise."
"Oh—I'm sorry, Mr. Doom." Dumbledore shook his head, sighing. "I'm afraid we're both telling the truth, and no one has used a Time Turner. Today is July 30, 1991. I am Albus Dumbledore, the current headmaster of Hogwarts, and Professor Phineas Black was headmaster two terms before me."
"So, what you're saying is..." Ivy looked incredibly surprised.
"That's right, all your classmates, friends, and professors are no longer here."
"I'm one hundred and forty-four years old?"
The two of them spoke at the same time, and then both fell into an awkward silence.