The person is at Hogwarts, but the system is in Middle-earth!

As the three of them passed through the wooden door, a nauseating stench immediately assaulted their senses.

[Environmental Warning: High Concentration of Toxic Gas]

[Source: Troll Body Odor]

[Recommendation: Hold your breath or wear a gas mask (if not equipped)]

They had to cover their noses, their eyes watering from the fumes. By the dim light of the fire, they could make out the contents of the room.

There lay a gigantic monster, unconscious. It was a size larger than the one the three had fought in the girls' restroom, a mountain of flesh blocking the center of the room. A large, bloody lump swelled on its head; it lay sprawled on the floor, clearly having been dealt with by the previous visitors.

Rowe stepped forward and kicked the troll's rough skin with his toe.

Enemy Unit: Moria Cave Giant (Elite)

[Status: Coma (Severe concussion)]

[Damage Analysis: Suffered a high-intensity blunt force impact. Possibly caused by some kind of dark magic.]

"Looks like someone cleared the roadblocks for us." Rowe looked around warily, his wand still in his hand. "And the methods were brutal. This wasn't a simple stun spell; it was a direct, violent knockout."

"Thank goodness we don't have to fight it again." Harry stepped over the troll's thick legs with lingering fear. "Let's go, I can't breathe."

They carefully bypassed the giant and pushed open the next door.

However, the moment they stepped across the threshold, a purple flame erupted from the doorway behind them, instantly blocking their escape route. At the same time, black flames also ignited at the doorway leading forward.

They were trapped.

[Scene Loading: Isengard Alchemy Laboratory]

[Environmental Effect: Toxic Steam - Deducts 1 HP per second (Sanity decreases slowly)]

[Warning: Barrog Fire behind - impassable]

[WARNING: The Black Flame of Mordor Ahead - Impassable]

The room was empty except for a long table with seven bottles of different shapes arranged on it. Beside it lay a piece of parchment with elegant handwriting.

"Look at this!" Harry picked up the parchment and read it by the firelight. "Danger is ahead, safety is behind, and two of us can help..."

Luo Wei leaned over and took a look.

This is a riddle poem.

"It's logical reasoning." Hermione's eyes lit up. "This isn't magic, it's logic! Many great wizards don't have even a tiny bit of logical thinking. If they can't deduce it, they'll be trapped here forever."

"Or they might be poisoned." Rowe stared at the bottles. In his system, each bottle had a red danger label floating above it.

In his eyes, this was not Professor Snape's riddle at all, but clearly an alchemical trap left by Saruman.

First bottle: [Liquid mercury (highly toxic)]

Second bottle: [Orc's Berserk Blood (Causes confusion upon consumption)]

The third bottle: [False Hope (Nettle Wine)]

...

"They want us to use our brains, not magic..." Hermione began pacing around the table, muttering to herself, pointing at the bottles with her finger. "Three are poison... two are wine... the remaining two..."

[Teammate "Elf Scholar" detected using the skill: Erudition]

[Puzzle progress: 30%... 60%... 90%...]

Lowe didn't disturb her. He leaned against the table, facing the purple wall of fire, watching warily for any shadows that might appear in the flames.

"Found it!" Hermione suddenly exclaimed excitedly.

She pointed to the smallest bottle in the row: "This bottle will allow us to pass through the black flames and retrieve the magic stone."

Then she pointed to a round bottle on the far right: "This bottle will allow us to pass through the purple flames and go back."

Harry stared at the small bottle, his face suddenly turning pale. "This... there's only enough for one mouthful."

Hermione paused, examined the small bottle closely, and her expression changed. She nodded, her voice lowering, "Yes, it's only enough for one person."

"Um..." Harry swallowed hard, looking at the round bottle, "What about the potion to go back?"

"There's only one bite." Hermione bit her lip, her eyes starting to redden. "The person who designed this level calculated the portion size perfectly. This isn't just a logic puzzle; it's... it's a test of humanity."

Rowe looked at the two bottles, then at Harry and Hermione.

A selection box pops up on the system interface:

Current drug inventory:

Advancement Potion (Mordor Pass): 1 unit

[Retreat Potion (Return to Shire): 1 dose]

Team size: 3 people

Logical conclusion: Someone must stay.

This is an unsolvable arithmetic problem. Three people, two doses of medicine, a perilous road ahead, and a long road behind.

Harry and Hermione both looked at Rowe. Their eyes were filled with helplessness and fear. After all, they were still just eleven-year-old children in this underground labyrinth of magic and monsters.

"I think I know what to do." Lowe took a deep breath and broke the silence.

He walked to the table, deftly picked up the round bottle and handed it to Hermione, then stuffed the small bottle into Harry's hand.

"Harry, drink the small one and stop those who come in before us. It is your duty, Ringbearer."

"Hermione, you drink the big one, go back and take Ron out, then go to Owlshaw to deliver a message to Dumbledore. We need Gandalf."

"And what about you, Rowe?" Hermione didn't take the bottle; instead, she turned to Rowe, looking at him in horror. "We're out of potions! What are you going to do?"

"Yeah, Rowe!" Harry chimed in, "We can share..."

"It's no use." Luo Wei shook his head. "The dosage isn't enough. Sharing it will only burn us all to ashes."

He paused for a second, glancing at the churning purple wall of fire.

"I don't need the medicine."

"Are you crazy?! You'll die here!" Hermione screamed, tears finally streaming down her face. "This fire...this is magical fire!"

"This fire is really powerful." Rowe looked at the churning purple flames and felt the heat wave hitting him. "That's why I'm not going anywhere."

"I will stay here."

"Stand here?" Harry was stunned.

"If enemies catch up, or if that giant that wasn't completely unconscious wakes up, or something else..." Rowe's voice echoed in the empty room, "if they want to find you in the back and interfere with you, they'll have to step over my corpse first."

[Speech Certification: A Great Success]

[Gain Buff: Hero's Back View (Charisma +5, Teammate Morale +100%)]

In fact, Luo Wei had a very clear plan in mind:

Behind the black flames lies the final boss battle (Quirkhor/Voldemort). Going there would be suicide. That level of battle is beyond the reach of a "half-baked Maiar." That's Harry's "destined one-on-one duel."

He couldn't get past the purple flames either (he didn't have enough medicine), and forcing his way through would just be suicide.

Staying here is actually the safest option.

First, you don't have to face the boss or the unknown risks outside.

Secondly, if a teacher (such as Dumbledore) comes to the rescue, he, as the person guarding the last line of defense, will definitely be the first to be saved.

Third, there are tables here that can be used as cover.

But in Harry and Hermione's eyes, what a heroic and tragic decision it was!

He gave the chance to survive to his companions and the glory of advancing to Harry, while he himself chose to stay in this deadly place filled with poisonous gas and raging fire, facing the possible pursuers and loneliness alone.

"Love..." Hermione sobbed uncontrollably. She rushed forward and hugged Love tightly. "You're a great wizard, Love Baskin. You're the pride of Hufflepuff."

"I am a soldier, ma'am." Rowe patted her on the back. "In war, someone always has to cover the rear. Go, don't let my sacrifice be in vain."

He pushed Hermione towards the purple flames: "Let's go, quick!"

Hermione drank the potion with trembling hands, took one last deep look at Rowe, and then turned and walked through the purple flames.

"You go too, Harry," Rowe said without turning around. "Don't look back."

Harry gripped the small bottle tightly, his palms sweating. He stared at Rowe's retreating figure, which, though not particularly tall, now appeared to him like a towering mountain.

"Be careful," Harry said in a trembling voice. "I'll be back."

"Go, Frodo," Rowe whispered, adding in a voice only he could hear, "This is my Helm's Deep."

Harry tilted his head back and drank the potion, took a deep breath, and resolutely stepped into the black flames, his figure disappearing instantly into the firelight.

Only Luo Wei remained in the room.

The sound of the flames burning became clearer.

Lowe stood in that heroic posture for a while, making sure they were all far away, before letting out a long sigh of relief and collapsing to the ground like a deflated balloon.

"I'm exhausted..."

He wiped the sweat from his forehead, pulled a flattened pumpkin pie from his pocket (which he had casually tucked away at dinner), and took a big bite.

[Stamina recovering...]

"System, open the tactics panel."

[Current Quest Branch Update: Guardian of Lonely Mountain]

Objective: Hold the position until reinforcements (Dumbledore) arrive.

[Remaining Time: Unknown]

[Enemy Unit Detection: None]

He set up a makeshift alarm trap at the doorway, moved the alchemical table across the center of the room, and hid behind it.

"Come on, you monsters and demons!"

"Think about this door? Ask the guy in my hand if he'll agree first."