Down to the Lake

Saturday.

Five in the morning.

Zhang Wen woke before his alarm went off.

He had slept poorly. He had probably only gotten a little over four hours of broken sleep. The operation plan had kept running through his mind—Line A captured the target, Line B went underwater, a fifteen-minute window, Basilisk Fang, Bubble-Head Charm, Iron Armor Charm—

He got up, washed his face, and changed into his combat gear. A layer of thin iron plates had been sewn into the Inner Layer of his dark gray robe—Filius Flitwick had helped enchant them with a weight-reduction spell. They weighed about as much as ordinary fabric, but offered additional protection against corrosion.

The Basilisk Fang was stored in an iron box at his waist. The Communication Lens hung from his ear. His wand was tucked into the bracer on his right arm.

Zhang Wen opened the door.

Someone was already in the corridor.

Artoria leaned against the opposite wall with her arms folded and her eyes closed. She wore a deep blue combat uniform, her golden hair tied in a high ponytail, with the invisible Excalibur hanging at her waist.

She opened her eyes at the sound of the door.

"You're earlier than me," Zhang Wen said.

"Four fifty."

"You're ten minutes early."

"So are you."

They looked at each other for a second.

"Let's go," Artoria said.

The Great Hall was empty. Hogwarts at five on a Saturday morning was deserted; even the ghosts had not risen for their rounds yet.

The kitchen elves had already prepared breakfast—they had been notified in advance. Two sandwiches, two cups of hot tea, and four Chocolate Frogs.

"You need to eat well before an operation." Artoria stuffed the second sandwich into her mouth so quickly that Zhang Wen doubted she had chewed at all.

"You didn't have dinner last night?"

"I did. But that was eight hours ago."

Zhang Wen watched her demolish the food with astonishing efficiency. Sandwiches, Chocolate Frogs, tea—all gone within three minutes.

"Do you want another serving?"

"No. Eating too much before battle will affect flexibility during underwater operations." Artoria wiped the corner of her mouth with a napkin. "Are you done?"

Zhang Wen looked at the sandwich on his plate, which he had taken two bites from.

"Not much appetite."

"Eat it."

"I—"

"Your physical reserves are already inferior to mine. Going underwater on an empty stomach could cause hypoglycemia and affect the stability of your spellcasting."

Zhang Wen sighed and shoved the sandwich into his mouth.

It did not actually taste bad. He simply could not taste anything when he was nervous.

"Eat the Chocolate Frog too."

"Are you my nutritionist?"

"I'm your partner. A partner's duties include ensuring your combat readiness."

Zhang Wen ate the Chocolate Frog as well.

Artoria nodded in satisfaction.

That nod—perhaps three millimeters at most—was the equivalent of a radiant smile in her system of expressions.

Six o'clock.

Third-Floor Corridor. Harry was already waiting.

He wore a thick sweater and waterproof cloak, carrying a birdcage with a Silencing Charm boundary cast around it. The rooster inside was quietly pecking at kernels of corn.

"Potter," Zhang Wen said as he checked Harry's equipment. "Communication Lens?"

"Here." Harry pointed to his ear.

"Emergency Floo Powder?"

"Here." Harry patted his pocket.

"Your assignment?"

"Wait on the north shore of the lake. Once I receive the signal, remove the Silencing Charm from the rooster's cage. If I receive the order to retreat, immediately use Floo Powder to return to Angus's home."

"Good."

Harry looked at Zhang Wen and Artoria. There was worry in his green eyes, but even more trust.

"Good luck."

"We don't need luck," Artoria said. "Preparation is enough."

Harry could not help smiling. "Professor Pendragon, that was really cool."

"I merely stated a fact."

The three of them traveled to Inverness by Floo Powder.

Seven fifteen. Glenmore Lake.

The Scottish Highlands in late November were as cold as a freezer.

A thin mist drifted over the lake. The water was gray-black, and the bottom could not be seen. The mud along the shore had frozen hard and crunched beneath their feet.

Angus was waiting by the lake. She wore three sweaters and a knitted cap, her nose red from the cold.

"You're here." She rubbed her hands together. "It's even colder than last week. The lake almost froze over."

"Has the Dubh-Loch Beast shown any unusual activity?" Zhang Wen asked.

"Yesterday afternoon, during its peak period, it churned around in the middle of the lake for a long time. Lots of bubbles came up. There was more movement than before."

The disturbance had grown stronger. That meant the Dubh-Loch Beast's magic was still increasing.

Fortunately, today would be the end of it.

Zhang Wen surveyed the area.

The north shore of the lake was a gentle slope—Harry's standby position. It had a clear field of view and was about twenty meters from the water, far enough to be safe.

There were several large rocks on the eastern shore—possible cover during a retreat.

The area north of the lake's center—the target location. The approximate position of the cursed stone.

"Harry, get in position."

Harry carried the birdcage and ran toward the slope on the north shore.

"Angus, go home."

"I want to—"

"You're not combat personnel. Go home and wait for news."

Angus hesitated, then nodded and left.

Only Zhang Wen and Artoria remained by the lake.

Zhang Wen opened the Line A channel on his Communication Lens.

"Headmaster Dumbledore, Line B is in position."

Three seconds later, Dumbledore's voice came through.

"Line A has finished deploying around the perimeter of Lestrange Old Manor. Moody is inside the manor. The Tracking Charm has been activated. We are waiting for the target to appear."

"Received. Line B standing by."

Zhang Wen closed the channel and checked the time.

Seven twenty.

There were nearly eight hours until three in the afternoon.

"What do we do now?" Artoria asked.

"Wait."

Waiting was the hardest part of every operation.

Eight hours of waiting.

Zhang Wen and Artoria sat down behind a large rock by the shore. The rock was sheltered from the wind and blocked the cold gusts blowing in from the north.

Zhang Wen cast a small Warming Charm, creating a faint layer of warmth around them.

"Eight hours." Zhang Wen leaned against the rock. "How do you plan to pass the time?"

"Meditate. Conserve strength."

"Meditate for eight hours?"

"As a knight, pre-battle meditation is a basic skill. I once meditated on Camelot's walls for sixteen hours while waiting for the Saxons to attack."

"Sixteen hours." Zhang Wen shook his head. "I couldn't do that."

"You can do something else."

"Such as?"

"Review the essentials of underwater spellcasting. Check your equipment. Or—"

Artoria paused.

"Or what?"

"Or sleep for a while. You didn't sleep well last night. There are dark circles under your eyes."

"You looked at my eyes again."

"Observing my partner's physical condition is a basic duty."

"Do you watch your other partners this closely too?"

Artoria did not answer that question.

"You should catch up on sleep," she said. "This afternoon, you will need to maintain at least fifteen minutes of intense focus underwater. Lack of sleep will affect your performance."

"Sleep beside an icy lake?"

"The Warming Charm covers enough space. And—"

She hesitated for half a second.

"You can lean against me."

Zhang Wen's heart skipped a beat.

"It worked well last time on the windowsill." Artoria's tone was utterly calm, as if she were delivering a weather report. "You slept against my shoulder for six hours. You didn't wake up once. That indicates the position was sufficiently relaxing for you."

Zhang Wen stared at her for three seconds.

Her expression did not change at all.

But the tip of her right ear had turned red.

Only a little. It was nearly invisible beneath her golden hair.

"You remember very clearly," Zhang Wen said.

"My memory has always been good."

"What else do you remember?"

"A lot." Artoria turned her gaze toward the lake. "You put two spoonfuls of sugar in your tea. You bite the cap of your pen while grading assignments. You rub your temples when you are thinking. When you are nervous, the index finger of your right hand taps the table unconsciously. When you look at me—"

She stopped.

"What happens when I look at you?"

"When you look at me, you smile. Only slightly. The corners of your mouth rise by about two millimeters. You may not have noticed it yourself."

Zhang Wen truly had not noticed.

"You observe too closely."

"Observing one's partner—"

"If you say 'basic duty' one more time, I'll push you into the lake."

The corner of Artoria's mouth twitched.

"Fine. Then I'll put it another way."

"What way?"

"I want to observe you."

Five words.

After saying them, Artoria continued looking at the lake, her expression unchanged.

But Zhang Wen noticed her hand—her left hand resting on her knee—her fingers curled slightly.

The King of Knights was nervous.

"I want to observe you too," Zhang Wen said.

Artoria said nothing.

But her fingers relaxed.

The two sat leaning against the rock. Cold wind howled overhead. The Warming Charm formed a small pocket of warmth around them.

About a minute later, Zhang Wen felt a light touch against his right shoulder.

Artoria's shoulder had moved closer.

Not resting on his shoulder—their shoulders pressed together. Side by side, equal contact.

The silence shared by two warriors before battle.

"Sleep," she said. "I'll keep watch. I'll wake you at two thirty."

Zhang Wen closed his eyes.

He thought he would not be able to sleep.

But Artoria's shoulder beside him—steady, constant, warm—put him to sleep within three minutes.

"Zhang Wen. Two thirty."

He opened his eyes.

His first sensation—his neck didn't hurt. This time, he had leaned against a rock with a shoulder cushioning him, so his sleeping position had been much better than last time.

His second sensation—warmth. The Warming Charm was still working, but the main source of heat came from beside him. Artoria's body temperature. She had not moved from her position for seven hours.

His third sensation—clarity. He had slept for nearly seven hours. He felt ten times better than he had that morning.

Artoria stood up. Her movements were far more agile than anyone who had been sitting for seven hours should have been.

"Your shoulder isn't sore?" Zhang Wen asked.

"My muscular endurance can support a stationary posture for over twenty-four hours. Seven hours is nothing."

"You really sat there for seven hours? Without moving?"

"Your head tilted over twice in the middle. I adjusted my angle so you wouldn't slide down."

Zhang Wen imagined the scene—Artoria sitting motionlessly behind the rock for seven hours, her only movement being a slight adjustment of her shoulder whenever his head tilted over.

"...Thank you."

"You're welcome. You look much better."

Zhang Wen stood and stretched his limbs.

Two thirty-five.

Twenty-five minutes remained before the operation began.

He opened the Communication Lens.

"Headmaster Dumbledore, Line B is ready."

"Line A is ready. Moody has set the trap spells on the third floor of the old house. The target has not appeared yet. Based on his usual pattern, he will arrive between two fifty and two fifty-five."

"Understood. Line B will wait for Line A's signal."

Zhang Wen switched to Harry's channel.

"Potter, how are you doing?"

"Cold. But alive." Harry's voice trembled slightly. "The rooster slept all morning and just woke up. It's in good spirits."

"Good. Remember, remove the Silencing Charm when you receive the 'activate' signal. Leave when you receive the 'retreat' signal."

"Understood."

Zhang Wen closed the channel.

He and Artoria walked to the water's edge.

The lake's gray-black surface was still and silent. There was no sign of any living creature. But more than ten meters beneath the surface, a monster mutated by Dark magic was waiting for its next command.

Zhang Wen took a deep breath.

"Final equipment check."

"Excalibur is ready." Artoria rested a hand at her waist. "Invisible Air can be maintained underwater, but its air-pressure effect will be reduced by around sixty percent."

"That's enough. Your task is to protect me. Once we find the stone, I'll destroy it."

"Understood."

"Bubble-Head Charm—" Zhang Wen raised his wand and cast one on Artoria first. A transparent bubble steadily enclosed her head. Her golden hair drifted slightly within it.

Then he cast one on himself.

"Iron Armor Charm." Both of them layered iron-reinforced Shield Charms over their bodies. A silvery-gray metallic sheen emerged across their skin.

"Hand mirrors." Zhang Wen handed a small mirror to Artoria and took another for himself. "Use these to watch behind you when underwater visibility is poor."

"Understood."

The two of them stood facing each other by the lake, fully armed. The bubbles of their Bubble-Head Charms trembled slightly in the cold wind.

Artoria looked at him.

Through two layers of transparent bubbles, her emerald-green eyes appeared especially clear.

"Zhang Wen."

"Hmm?"

"Yesterday's promise still stands."

The pinky promise.

"It still stands," Zhang Wen said.

"Good."

Artoria turned toward the lake.

Her hand drew Excalibur from her waist—though the blade was invisible beneath Invisible Air, Zhang Wen could still sense that familiar sharpness in the air.

"Wait for the signal," Zhang Wen said.

The two of them stood at the water's edge.

Cold wind. Gray sky. Silent lake.

The Communication Lens remained quiet.

Two forty-five.

Two fifty.

Two fifty-two—

"Line A calling Line B." Dumbledore's voice suddenly sounded. "The target has appeared. He has entered the old house and is heading for the third floor."

Zhang Wen's heartbeat quickened.

"Line B received. Waiting for confirmation of the arrest."

Thirty seconds of silence.

One minute.

Then—

Moody's voice burst out.

"Got him! Old Nott! You're under arrest! He's activating the crystal ball—Albus, pin down his hand—"

An explosion sounded in the background, followed by two muffled impacts of clashing spells, Moody's roar, and then the sound of metal striking the floor—as if a wand had been knocked away.

Five seconds later, Dumbledore's voice came through, calm and clear.

"Line A operation complete. Old Nott has been subdued. The crystal ball array has been severed."

Zhang Wen clenched his fists.

"Line B received! Operation begins!"

He looked at Artoria.

Artoria looked at him.

"Go," she said.

The two of them jumped into Glenmore Lake at the same time.

The instant they entered the water, cold surged in from every direction.

The Bubble-Head Charm kept the water out—their heads remained dry—but their bodies were submerged in lake water below five degrees Celsius. The iron coating from the Iron Armor Charm provided some insulation, but it was still cold enough to make their teeth chatter.

Zhang Wen used Lumos to illuminate the surroundings.

The lake water was murky. Visibility was around three meters. Beyond that lay nothing but gray-black chaos.

Artoria was one meter to his right. Her movements were incredibly efficient—her body almost horizontal, her limbs moving only slightly yet generating tremendous propulsion. She adapted to the water far faster than Zhang Wen did.

The two of them began diving toward the north side of the lake's center.

Three meters. Five meters. Eight meters.

As they descended, the light grew dimmer and dimmer. Zhang Wen's Lumos spread into a hazy ball of white light in the water, illuminating no more than two meters around them.

The water pressure began increasing. A faint swelling pain pressed against his eardrums.

Ten meters.

Zhang Wen checked the Communication Lens—the signal degraded severely underwater, but short-range communication could still barely be maintained.

"Artoria, can you hear me?"

"I can. Weak signal. Keep communications brief."

"Understood. The target area should be around twenty meters ahead. Watch your footing—the stone may be buried in the silt on the lakebed."

"Understood."

Twelve meters.

The lakebed came into view.

Gray silt and gravel. A few scattered strands of dead aquatic grass. Several irregular stones.

No fish. No living things at all.

The Dubh-Loch Beast's presence had completely killed the surrounding ecosystem.

Zhang Wen scanned the lakebed with his wand. The Tracking Crystal fragment Filius Flitwick had given him was embedded at the tip—it could detect concentrations of Dark magic energy.

The crystal fragment began emitting a faint purple glow.

Direction—slightly left of straight ahead.

Zhang Wen made a gesture. Artoria nodded, adjusted course, and took the lead three meters ahead of him.

The two of them moved forward close to the lakebed.

The purple glow grew stronger and stronger.

The concentration of Dark magic energy was rising sharply. Zhang Wen could feel a cold, oppressive presence coming from ahead—similar to the feeling of the Basilisk in the Chamber of Secrets, but wetter and more viscous.

Then he saw it.

Embedded in the silt on the lakebed was a fist-sized black stone.

The stone's surface was pitch-black and glossy. The surrounding silt had turned an unnatural deep black, spreading outward in a radius of around one meter. Faint runes covered the stone—or rather, they had once been runes. They had now been corroded by Dark magic energy until only blurred grooves remained.

That was it.

The cursed stone. The source of the Dubh-Loch Beast's magic.

Zhang Wen signaled Artoria: "Target found."

Artoria nodded. She adjusted her position to face outward, Excalibur held across her body—a defensive stance. She protected Zhang Wen's rear.

Zhang Wen took an iron box from his waist, opened it, and removed a Basilisk Fang.

The fang still emitted a faint poisonous glow underwater. Its tip was sharp. It was the deadliest legacy left behind by the King of Basilisks.

He swam above the stone and adjusted his angle.

The fang aimed at the stone's surface.

He took a deep breath—the air inside the bubble.

He raised his arm.

Ready to drive it down—

Artoria suddenly spun around, grabbed Zhang Wen's shoulder, and yanked him backward.

At that exact moment.

The spot where Zhang Wen had just been was violently pierced by a pitch-black tentacle.

The silt on the lakebed exploded upward.

The Dubh-Loch Beast had arrived.