Chapter 119: The Marauder

"Don't think this is just an ordinary old parchment," George said. "Just do this."

He lightly tapped the parchment with his wand and said, "I solemnly swear I am up to no good."

After a moment, faint ink lines began spreading like a spiderweb, crisscrossing every corner of the parchment; then a line of large letters appeared at the top, curling green script blooming like flowers, declaring:

Moony, Wormtail, Padfoot, and Prongs

For the assistance of magical pranksters everywhere

Proudly presented

The Marauder's Map

"Well?" George said proudly. "This map shows every detail of Hogwarts, including the castle and all the secret passages."

"But the truly amazing part is that it tracks everyone's movements," Fred pointed at the map. "Look, Professor Dumbledore is pacing in his office, Mrs. Norris is sneaking around the second floor looking for food, Peeves is hopping around the trophy room..."

Harry didn't hear a word of it; his entire attention was fixed on the four names. Cavendish's words surfaced again in his mind.

"Prongs, James; Padfoot, Sirius; Moony, Remus; and Wormtail, Peter."

These were the belongings left behind by his father and his schoolmates.

"Thank you, George, Fred," Harry said, struggling to steady his trembling voice. "This means everything to me."

"Of course," Fred said, seemingly oblivious to Harry's emotion, continuing on his own. "But if you want to hide it—"

With this small spell, the ink lines on the Marauder's Map vanished, leaving only the worn piece of parchment.

As the charm took effect, the ink lines vanished, leaving only the worn parchment.

"Now then, young Harry," George mimicked Percy's pompous tone, "mind your manners."

The twins left the room, thoroughly pleased with themselves. Harry clutched the map tightly to his chest, vividly imagining how his father must have roamed the castle in his youth, full of daring schemes with his friends. The faces he had seen in the mirror and the afterlife reappeared before him—as if James were holding his hand, guiding him through the ancient halls, grinning mischievously all the while.

But one thought lingered, stubborn and unshakable: Sirius's betrayal. Harry sighed. If he ever got the chance—or made a plan—he would not let that traitor go unpunished.

"I solemnly swear I am up to no good," Harry whispered, scanning the magical map.

Very quickly, he noticed a problem: he could not find Professor Lupin.

It was not a full moon, yet he found no trace of Remus Lupin's name—in the Defense Against the Dark Arts classroom, the professor's office, any other staff room, or even the student dormitories.

Perhaps the map cannot track the four founders, Harry thought silently. They must have left backdoors, in case the map fell into the wrong hands.

But that also meant he could not use the Marauder's Map to catch Sirius.

Harry carefully rolled up the map and returned to the common room. He knew it was time to begin drawing his own map.

For a long time afterward, Harry devoted himself entirely to studying the Marauder's Map, determined to understand the spells and principles behind it.

This annoyed Ron intensely. He sharply remarked, "The bookworm contagion has spread." Harry was mocked several times and had to bribe him with secret Honeydukes stock to make him drop it.

Finally, after Harry's relentless research and several Torchwood discussions, they settled on the design for their own map.

Harry was certain the original Marauder's Map used a powerful "Trace Charm," one that revealed the location of every person within its range and could identify Animagi, Polyjuice Potion disguises, and all forms of invisibility.

But the Trace Charm had many flaws: it could not distinguish between people with identical names (common in Britain, where fathers and sons shared names), and once someone left the map's range, their name vanished.

Torchwood's children believed a 3D map could solve these issues perfectly—binding the Trace Charm with Transfiguration to turn ink dots into miniature human figures. Those in disguise would still appear as their true selves, but with a translucent phantom overlay above their heads to indicate deception. For those who left the school, their miniature figures would remain frozen at the exit they last passed through.

Luna had fully mapped out the staircases' movement patterns; Cui Ge had located nearly all the secret passages; Harry had shared the Marauder's Map's corridors with him as a supplement. Since the original map did not include the Chamber of Secrets, they agreed to add the room that had plagued them all year.

With all preparations complete, the next challenge was the spells. The children were not yet skilled enough; many ideas proved difficult to realize.

But Torchwood was not made up solely of young students. Harry sent Hedwig back to Tang Dun to retrieve Tom Riddle's diary. In front of everyone, Tom generously shared numerous practical magical tricks.

"I suggest we keep Tom's diary in headquarters and display it publicly," Cui Ge said. "Everyone can ask him questions anytime. He can serve as Torchwood's advisor."

Tom offered no objection. The children sealed him in a glass display case, cast a joint spell to lock it, and placed a Quick-Quotes Quill beside it—so anyone could ask him questions, but no one could secretly take the diary away.

To supplement the original Trace Charm, Harry used the Invisibility Cloak's advantage to cast tracking charms at multiple locations across Hogwarts, enabling real-time imagery to generate more lifelike miniature figures or confirm disguises.

Cui Ge had originally suggested adding a recording and storage function, but Ginny had rejected it once. Now, as the map neared completion, they realized implementing it was far more difficult than expected.

For now, Torchwood's version of the Marauder's Map was merely an improved exterior version of the original, with some patches added. To achieve more functions, even with Tom's help, their spellcraft was still insufficient.

Before Christmas, they used the holiday break to enthusiastically complete all work. But once everything was finished, a strange feeling settled over them all. Harry precisely named it: "adorned in fine clothes, walking unseen."

"I think we should invite someone to see it," Cui Ge said excitedly. "If I could, I'd even want my mother to come."

"Hmm," Harry hesitated. "I originally planned to invite the students from the Forbidden Forest last term. But that would risk Torchwood's secrecy."

"Then your mother is the perfect choice," Malfoy smiled. "She won't blab, and we'd be delighted to show her Torchwood's great achievements."

On the eve of Christmas Eve, Harry waited with Ginny and Ivy on the fourth-floor corridor. Their new headquarters was hidden somewhere along it.

Soon, Pansy and Luna arrived, followed by Malfoy, who was scolding Crabbe.

Finally, Cui Ge led a tall girl up the stairs. Mrs. Fontroy had dyed her hair gold and wore a Slytherin uniform—she looked radiant, like a seventh-year prefect.

"Cassandra," Malfoy pronounced the mistaken name with mock solemnity. "Welcome to Torchwood's headquarters."

Before a bare wall, he raised his wand and said: "For you, I have returned."

The wall became unreal, shimmering like mist. With a light tap of his wand, a doorway appeared.

Inside was a cozy parlor: plush armchairs sat atop thick wool rugs, a long tea table held teacups and fruit platters, and a massive dessert stand stood nearby.

In one corner stood a miniature model of Hogwarts Castle. This time, Malfoy yielded the spotlight to Cui Ge.

He raised his wand before the model and declared loudly: "For Hogwarts!"

One by one, miniature figures appeared around the castle—each a scaled-down version of those present. The bespectacled miniature Harry raised his wand first toward the sky; the red-haired Ginny followed. Their wands emitted nearly transparent pale beams, and finally, the miniature Malfoy's beam merged with them. A ripple, like a protective shield, slowly descended.

"Now we can use this model to view any corner of the castle, from any angle, and hide any wall," Cui Ge said, waving his wand. Half the castle vanished, revealing a cross-section.

Tiny figures bustled within: house-elves preparing food in the kitchen, children laughing and playing in the common room, professors either nervously preparing lessons (like Lupin) or snoring soundly (like Hooch).

"Wonderful, children," Mrs. Fontroy exclaimed. "You're brilliant."

"Let's show you the meeting room," Cui Ge said, tapping his wand again and murmuring: "No one can run forever."

The shield rose again; the model returned to its inert state.