My understanding is incredible, I built a floating city in Hogwarts

Finally, the elevator stopped, and an indifferent woman's voice rang out: "Department of Mysteries." Then, the fence door slid open, and they stepped into the hallway outside.

There was silence all around, except for the nearest torches, swayed from side to side by the air whistling from the elevator, casting dappled light and shadow.

Harry's heart raced as he turned to the all-black door. For many months, the door had been appearing in his dreams, and now he was finally standing in front of it.

"It should be this way. Harry whispered, taking the lead in the hallway, followed by the rest of the group silently.

Harry walked towards the door, nervous and expectant. As in a dream, when he touched the doorknob, it opened softly. He took a deep breath and took the lead in striding across the threshold.

They stood in a large circular room, every inch of space shrouded in a deep black, as if even time had stood still. The floor and ceiling are all breathtaking black, like an endless night sky, both deep and mysterious. The surrounding walls are inlaid with doors that are also pitch black, they are indistinguishable, like a silent black hole of "five, six, seven", without any markings, even the handles are hidden in the dark.

The walls are occasionally dotted with a few branch-like candles, in which blue flames leap and flicker. The cold blue light is projected on the smooth marble floor, reflecting the sparkling waves, giving the illusion of being in the depths of the lake.

"Remember to close the door. Ron's voice rang softly in the quiet of the space, as if it was afraid of disturbing the sleeping darkness.

Neville did as he was told, the torch-lit hallway slowly closing behind them, and the only ray of light vanished. The room plunged into deeper darkness, leaving only the trembling blue flames on the walls and the eerie shadows they cast on the ground, wandering like ghosts.

In Harry's dreams, he was always able to walk through the room without hesitation, towards the door that faced the entrance. However, at this moment, facing the twelve doors in front of him, he felt a sense of confusion. He scrutinized each door, trying to find the one that led to his destination.

Ginny clutched her brother's arm, her eyes revealing a deep unease, as if fearing that the floor in the darkness would spin like a wall. However, the floor is as solid as ever.

At this moment, a loud rumbling sound suddenly sounded, which shook people's hearts. The flame of the candle began to shake violently, as if driven by some force. Immediately afterward, the circular wall slowly rotated.

Ginny subconsciously grabbed her brother's arm tighter, panic written all over her face. However, the floor remained rock solid and showed no signs of shaking. For a few seconds, the walls spun at an alarming speed, and blue flames danced wildly around them, blurring into a brilliant light and shadow, as if countless neon tubes were intertwined and flickering in the darkness.

Then, as abruptly as it had begun, the rumbling came to an abrupt halt. The walls stopped spinning, and everything returned to calm.

Harry's eyes flashed with blue bands of light, and there was nothing else in his field of vision, which made him feel a little confused.

He looked around and asked uncertainly, "Which door shall we enter?"

"That's the ...... over there," Neville was about to speak, but was glared back by a stern look from Ginny, who immediately shut his mouth.

Ron noticed Neville's actions, he followed Neville's gaze, then turned to Harry and asked, "Harry, what did you see in your dream?"

Harry swallowed, trying to remember the sight in his dream:

"In my dream, I got out of the elevator and through the door at the end of the hallway, and into a dark room that was exactly like this one. Then, I walked through another door and entered what looked like a ...... It's like a glowing house. We should try a few doors," he said, growing faster, "I'll know if we find the right one." Hurry!"

As he spoke, he strode to the opposite door, followed by the others.

Harry placed his left hand on the cold, shiny door and raised his wand, ready to strike as soon as the door opened. Then, he gave it a hard push.

The door opened, and they were immediately shocked by what they saw.

After the darkness of the first room, the rectangular room looked much brighter, with a soft glow from the few lamps hanging from the ceiling with gold chains. However, there were none of the flickering, flickering lights Harry had seen in his dreams. The room was empty, except for a few tables sitting alone.

In the center is a huge glass water tank, and the dark green liquid inside emits a faint glow. Many pearly white things float lazily around in the water, as if it were a peaceful marine world. They stared at the mysterious tank, their hearts filled with doubts and curiosity.

Neville curiously leaned close to the tank, his eyes pressed against the walls and peeked inside. The things floating in the green liquid emit an eerie glow, they flicker and flicker, and they are strangely shaped, like slimy cauliflower dancing in the deep sea.

Harry took off his glasses, gently wiped them with his sleeve, and put them back on, staring at the strange sight inside the tank. He turned to his companions and asked, "Are these things a special kind of fish?"

The corners of Neville's mouth turned up slightly, revealing a hint of innocent curiosity, "Can they eat them?"

Ginny immediately frowned, and snorted coldly and reminded, "Stupid, these things are not fish, they are brains! I've seen something similar in Levin's book." Don't touch them, or they will entangle you with the tentacles of your thoughts and leave indelible scars on your spirit. I don't want to put the Doctor's Oblivion ointment on your fat body. "

Neville shrugged his shoulders and took a few steps back, keeping a certain distance from the tank, muttering, "Got it, don't be so fierce." "

Harry clapped his hands and looked around, "We need to get out of here, something is wrong here." We need to find another door to try. "

They turned back to the dark round room, Ginny walked last, and before leaving, she raised her wand, streaked a mysterious symbol in the air, and whispered, "[Mark], appeared!" Immediately, a fiery red X appeared on the door she had just walked through, as if it was a flame burning in the darkness....

The door slammed shut, followed by a loud rumble.

The walls began to spin rapidly again, but in the chaotic blue, the blurred golden red stood out. When everything was still, the fiery X was still burning on the door, reminding them that the door had been tried.

Harry hurried to the mysterious door opposite, followed by the others. He gripped his wand tightly, prepared briefly, and slammed the door open.

A cold air currents swept over their faces, and they found themselves in a space that was even larger than the room they had just had. In the dim light, the rectangular room recessed in the center, forming a huge stone crater about twenty feet deep. They stood on the top benches on the top floor, and they could clearly see the stone benches extending down at a steep angle, like an old circular theater, and reminded Harry of the courtroom at the time of the Wizengamot trial.

However, unlike the courtroom, there is no chained chair in the center of this pit. Instead, there is a raised tall stone platform on which an ancient and dilapidated stone arch is erected. There is no wall around the arch, only a tattered black curtain or draperia hangs from it. Although there was not a hint of breeze in the cold air, the drapery fluttered gently, as if someone had just touched it.

Ron couldn't help but be curious, and he quickly jumped down the rows of stone benches to the bottom of the pit. He slowed down and cautiously walked towards the high platform, each step emitting a dull echo. From this point of view, the pointed arches appear even taller and more mysterious. The curtains were still swaying gently, as if telling some secret.

Ron suddenly had a strange feeling, as if something had discovered his 2.1 presence behind the arch and had developed an inexplicable attraction to him. He felt as if he was being pulled by an invisible force, wanting to go behind the arch and explore the unknown world. This abnormal sensation made him feel weird, his heart beat faster, and his palms sweated slightly.

Just as Ron was about to delve into the strange sensation, Harry's voice suddenly rang in his ears, breaking his musings.

"Ron, listen!" Harry nervously walked over to Ron, frowning as he stared at the gently fluttering drapery, "Someone whispered from behind there. Do you think it's going to be Sirius?"

Ron shook his head and replied affirmatively, "It can't be Sirius, Harry. Did you know that this curtain has a terrifying history? The curtain was even used as a death chamber for a time before the second Minister of Magic, Damocles, Rohr, took office in 1718 and made an agreement with the Dementors to use Azkaban to imprison and punish prisoners. Anyone who walks through the curtains, dies, without exception. "

The strange feeling seemed to be becoming more and more apparent, but no one seemed to be aware of it except Ron.