Exiting the time loop was simple: he just had to uncover the full truth behind the events.
For a first-year William, this might have seemed nearly impossible. But after two years in the loop, it was more than manageable.
Now William had identified four crime scenes: the Defense Against the Dark Arts office, Snape's potions storeroom, the entrance to the Ravenclaw common room, and the Room of Requirement.
He decided to stake out the Defense Against the Dark Arts office and wait for Tywin to appear.
This was, after all, where everything had begun.
The 740th Loop
Fully prepared, William hid alone in a shadowy corner near Tywin's office.
It was only 7:40 a.m.; the Quidditch match hadn't yet started, and Tywin was still in his office.
Having watched him numerous times, William knew Tywin would leave in about ten minutes, so he wasn't worried about him coming out unexpectedly.
From inside his robes, William pulled out a potion and drank it in one gulp. This was a special booster he'd "borrowed" from Madam Pomfrey.
To uncover the truth, he needed to tail Tywin without being detected, which meant using a Disillusionment Charm.
However, skilled wizards could still detect a basic Disillusionment Charm.
After many trials, William had found that only two things could reliably strengthen the spell's effectiveness: constant practice and boosters.
This particular booster was a specialized potion that enhanced other potions' effects, used by Madam Pomfrey only during critical procedures.
He knew about it from personal experience—after taking a nasty fall in a Quidditch match, Pomfrey had used the potion to amplify the effects of a Blood-Replenishing Potion for his injuries.
If there was one benefit of the time loop, it was that William had brewed and tasted nearly every potion in the textbook, gaining firsthand experience of their effects.
Having drunk the booster, William cast the Disillusionment Charm and settled into his corner, keeping the Marauder's Map ready in his hand.
The next moment, four dots labeled "Tywin" appeared on the map!
One was in the Defense Against the Dark Arts office, about to step out.
One was in the fourth-floor corridor, crossing paths with Dumbledore before both turned back toward the Headmaster's office.
One was lurking in a corridor on the fifth floor.
And one was swiftly moving toward the corridor leading to Ravenclaw Tower.
"Four Tywins…" William shook his head.
Although he had seen this before, it was still fascinating each time.
Now his task was to solve the mystery of the four Tywins and understand why they all appeared simultaneously in different locations.
Just as he had anticipated, the door handle of the Defense Against the Dark Arts office turned, and Tywin stepped out right on schedule.
He glanced around cautiously. Seeing no one, he clutched his wand and strode purposefully up the staircase toward the fifth floor.
William followed quietly, his heart pounding, despite having taken a Calming Draught earlier.
Fortunately, his steps were light, and Tywin didn't notice that he was being tailed.
As Tywin reached the fifth-floor corner, he was about to encounter the other Tywin.
But to William's surprise, it wasn't Tywin standing in the corridor. It was Professor Snape.
Or rather, someone who looked exactly like Snape—though on the Marauder's Map, his label still read "Tywin."
The map didn't lie, so he must have taken Polyjuice Potion.
As someone who'd used Polyjuice extensively to play on two Quidditch teams, William understood its effects all too well.
But the Tywin who'd left the office seemed unaware that the figure before him was, in fact, himself.
Intent on his mission, he assumed he'd been caught when he saw "Snape" in the corridor.
"Snape" seemed about to say something, but Tywin didn't wait. He raised his wand and shot a spell at the other man.
"Snape" dodged, then jabbed his wand forward and shouted, "Stupefy!"
Tywin quickly countered with his own spell.
"Snape" looked pale and injured, with multiple wounds slowing his reactions. It was clear he was no match for Tywin.
After a brief exchange, Tywin's spell struck "Snape" in the chest. With wide, horrified eyes, "Snape" was blasted backward, crashing against the wall and spitting up blood.
Grinning viciously, Tywin advanced, clearly intending to finish off his opponent.
It looked as though William was about to witness Tywin killing himself.
But "Snape" fired a spell at the column by his side, causing the wall to collapse and block the hallway between them.
Tywin paused, glaring through the rubble as "Snape" staggered toward the staircase. After a moment's hesitation, he turned and rushed up another flight of stairs, as though determined to complete his mission.
William broke into a run, keeping pace with Tywin while glancing at the Marauder's Map.
The Polyjuice Tywin wasn't heading to Dumbledore's office but toward the eighth floor—the Room of Requirement.
So that's why Tywin had struggled against Fluffy! Severely injured, there was no way he could stand a chance against a three-headed dog.
But William left that Tywin alone and continued following the original Tywin as he limped down the corridor, taking the shortest route toward Ravenclaw Tower.
He knew that another Tywin lay in wait up ahead.
As Tywin entered the corridor, his guard dropped, perhaps sensing he was near his destination.
Then, out of nowhere, a spell streaked toward him, barely missing his head.
"Who's there?" Tywin roared in fury.
But the ambushing "Tywin" paid no heed, casting spell after spell.
Caught off guard—especially upon seeing an exact double of himself—Tywin had no idea what was happening and quickly found himself outmatched.
After being hit by a spell, he turned and ran.
The ambushing "Tywin" laughed triumphantly before heading toward Ravenclaw Tower.
William knew this Tywin was going after the Ravenclaw ring. The path from here was clear of obstacles, save for Robert.
However, William continued tailing the original Tywin.
Dragging his injured body, Tywin slumped against a corner. Reaching into his collar, he pulled out a long, delicate gold chain, at the end of which hung a small, gleaming Time-Turner.
"Of course… it was this!"
William finally saw the proof he'd been looking for. This was how Tywin could appear in multiple places simultaneously.
A Time-Turner!
Professor Tywin twisted the Time-Turner counterclockwise once, vanishing from sight.
And then, one by one, all the other Tywins disappeared from the Marauder's Map, like streetlights going out in sequence.
This meant only one thing: Professor Tywin was dead.
William sat in silence for a long while, finally piecing together the entire mystery.
It was all perfectly clear.
Simple, even.
He finally felt ready to adjust a pair of nonexistent black-rimmed glasses, stand before Dumbledore, and proudly declare:
"Elementary, my dear Dumbledore!"
[tl/n: aah, sherlock holmes reference. Have a great day/night! and don't forget the powerstones!]
join my patreon for 70+ advanced chapters: patreon.com/HyppoTL