.. Mobile reading .. Wang Yu endured the suspicion in his heart and listened to the old Taoist's remnant soul as he continued to speak.

"Back then, this gray immortal woman named Mo Yu used a secret method to suppress her cultivation realm and aura to infiltrate my Underworld Frost Immortal Palace. Seeing her excellent talent, I had a moment of mortal desire and took her as a disciple, teaching her supreme sword techniques and imparting her spirit domain secret arts. But the result..."

Speaking of this, the old Taoist paused for a moment before continuing, "As a result, she tried to use the Immortal Palace as an entrance to open a passage to the Gray Realm, leading those Gray Realm creatures to invade the Immortal Realm. When I was fighting with her, the Reincarnation Hall, which had already colluded with the Gray Realm, took the opportunity to launch a large-scale attack on the Underworld Frost Immortal Palace, eventually leading to the loss of control of the war. Alas, it was truly tragic..."

"The Underworld Frost Immortal Palace was breached, and you were defeated!" Wang Yu suddenly opened his mouth and added.

"Defeated... Hmph, they didn't get any benefits in the end, did they? It's just a pity that my good Underworld Frost Immortal Palace was shattered into pieces. I'm afraid many areas have been completely lost." The old Taoist said with some regret.

"In your Underworld Frost Immortal Palace, is there a region called Cold Moon Realm?" Wang Yu suddenly remembered something and asked quickly.

"Cold Moon Realm... Of course, there is. Why do you ask?" The old Taoist's remnant soul raised an eyebrow and asked.

Hearing this, Wang Yu understood that this Cold Moon Realm was probably completely lost after that battle and drifted to the Spirit Realm, becoming a secret realm there.

If that's the case, the Myriad Swords Diagram he once obtained from the Cold Moon Realm probably originally belonged to the Wusheng Sword Sect.

"Boy, you've asked so many questions. Can I ask you a few questions too?" The old Taoist saw that Wang Yu didn't speak and didn't care. He asked with a chuckle.

"How did that battle end, and how did you get here?" Wang Yu turned a deaf ear and asked, unprompted.

"Alas, the situation is stronger than people. People's hearts are really not what they used to be..." The old Taoist was choked half to death, shaking his head and muttering.

Wang Yu was expressionless, and the long sword in his hand was never put away. At this moment, he weighed it slightly again.

"Cough... Speaking of how the battle ended, I don't know... After Mo Yu's Reincarnation Hall reinforcements arrived, I fought two enemies alone. After seriously injuring them, I was outnumbered and couldn't avoid defeat in the end. My physical body was destroyed... Helplessly, I, the old Taoist, escaped here with a wisp of remnant soul and sealed myself up, waiting for rescue." The old Taoist coughed dryly and said slowly.

"Oh, why didn't the Heavenly Court send troops to rescue? Aren't they always at odds with the Reincarnation Hall?" Wang Yu asked with a slight lift of his eyebrows.

"Hehe, although I was in charge of the Underworld Frost Immortal Palace back then, I was too used to being free and unwilling to register in the Heavenly Court, so I always listened but didn't obey their orders. When things came to a head, they were naturally happy to wait for both sides to suffer and then reap the benefits. If I'm not mistaken, the current Underworld Frost Immortal Domain has probably been completely taken over by the Heavenly Court, right?" The old Taoist chuckled and asked with a smile.

"The Underworld Frost Immortal Domain has been renamed the Northern Cold Immortal Domain. The current Northern Cold Immortal Palace is indeed under the jurisdiction of the Heavenly Court." Wang Yu nodded and said.

The old Taoist was slightly stunned when he heard this and stopped talking, falling into a long silence.

"Where did these sculptures come from?" Seeing this, Wang Yu put away the Azure Bamboo Bee Cloud Swords, looked around, and asked.

"I was bored, so I did some handicrafts to pass the time. How is it? Not bad, right?" The old Taoist suddenly chuckled and asked.

"Since you sealed yourself here, didn't you leave yourself a way out?" Wang Yu asked again.

"This place is originally a prison cell. I, the old Taoist, rushed in here in a hurry. How could I have time to arrange a way out?" The old Taoist raised an eyebrow and glanced at Wang Yu like he was an idiot.

"So, you don't know how to get out of this small secret realm?" Wang Yu asked after a moment of silence.

He could only believe at most 50% of what the old Taoist said. He always felt that the other party was hiding something, but he couldn't find any obvious problems for a while.

Hearing this, the old Taoist looked him up and down, shook his head, and tsked, "With your current strength, you want to go out? I'll give you two words - no way."

"Oh, why do you say that?" Wang Yu asked in confusion.

"After this secret realm is closed, it can only be opened from the outside. If you want to go out from the inside, there is only one way, and that is to directly break its operating core. But this core is related to the entire secret realm. Once attacked, it will gather the heaven and earth spiritual power contained in the entire secret realm to resist. If it was my previous cultivation level, it would be no problem, but you kid is at most at the early stage of Golden Immortal, right? Then don't even think about going out. Stay here honestly and keep me company." The old Taoist smiled and said.

"May I ask what realm your senior's past cultivation was?" Wang Yu suddenly changed his address and asked.

"Not high, not high. I, the old Taoist, was once a late-stage Grand Unity Jade Immortal." The old Taoist chuckled. Although he was only a wisp of remnant soul, a smug smile still appeared on his face.

Although Wang Yu had already guessed this, he couldn't help but feel a little shocked when he heard the answer.

"Then, according to what you said, I can only break the core of the secret realm if I reach the late stage of Grand Unity?" he asked.

"It doesn't necessarily need to be the late stage. The early stage of Grand Unity should be enough, but you kid... Oh, right, what technique are you cultivating? Have you mastered the power of laws?" The old Taoist asked halfway through his words.

"What does this have to do with breaking the core of the secret realm?" Wang Yu asked.

"It has a lot to do with it! If you are cultivating ordinary laws, then you naturally need Grand Unity... If you are cultivating one of the three supreme laws of time or space and can achieve some success, then you don't need to cultivate to the early stage of Grand Unity. The middle stage of Golden Immortal is enough. But how is this possible?" The old Taoist shook his head and explained.

"Could it be that the core of this secret realm is related to these two laws?" Hearing this, Wang Yu didn't rush to give an answer and continued to ask.

"The core of this secret realm is originally something that contains the law of time. According to my estimation, if you break it with brute force, you need the early stage of Grand Unity cultivation. If you deconstruct it with the law of space, you need the late stage of Golden Immortal cultivation. If you break it with the law of time, you only need the middle stage of Golden Immortal cultivation." After listening, the old Taoist said impatiently.

"May I ask where the core is located? I hope you can lead the way so I can take a look." Wang Yu thought for a while and said.

The old Taoist's remnant soul seemed a little hesitant and didn't speak for a long time.

"What's wrong? Is there something inappropriate?" Wang Yu asked with a slight frown.

"That place has some restrictions. My remnant soul body... is not suitable for going in." The old Taoist stuttered.

"This is easy to handle. Please stay in my soul-nurturing furnace for now." With that, Wang Yu flipped his palm and took out a delicate black-purple incense burner, only the size of a palm, made of soul-nurturing wood.

"Alright..." The old Taoist sighed softly, and his figure shrank into the incense burner like smoke.

"Please lead the way." Wang Yu said, holding the incense burner in his hand.

"There is a secret door on the left side of this hall. After entering from there, go straight ahead..." The old Taoist's voice came from the incense burner, sounding a little muffled.

Wang Yu had been releasing his divine sense to explore the surroundings and followed the old Taoist's guidance, heading towards the depths of the underground palace.

After walking through the maze-like tunnel for about an hour, he arrived outside another underground palace hall.

"Is this the place?" Wang Yu asked, looking around.

"The core of the secret realm is inside. I won't accompany you in. Just put me and this furnace outside the door." The old Taoist's voice came from the furnace.

Wang Yu's eyes lit up with azure light, sweeping towards the stone door of the hall. He saw that it was empty, without any restrictions or spiritual power fluctuations.

The corners of his mouth curled up. He raised his hand and tossed it. The purple-black incense burner in his palm spun and fell into the hall.

There was a soft "pop" sound.

The incense burner landed, and golden threads flowed out from the ground, emitting countless golden light traces, illuminating the entire hall.

"Damn kid, get me out quickly! If you're any later, I'm going to lose my soul..." A shrill cry came from the incense burner, and the entire voice became distorted.

Wang Yu looked at the golden patterns on the ground and the golden light scattered in the air. He found that it was as restrained against wandering souls and ghosts as the Evil-warding Divine Lightning. He waved his sleeve and pulled the incense burner back.

"Ouch... Ouch..." The remnant soul in the incense burner cried out in sorrow, and the light on his body became much dimmer. He looked like he was about to disappear into nothingness, and he didn't even seem to have the strength to curse Wang Yu.

Wang Yu didn't speak. He flipped his palm and pinched a talisman that stabilized the soul between his fingers, stuck it on the incense burner, put it casually outside the door, and stepped into the hall himself.

As soon as he entered, Wang Yu felt warmth all over his body. He then discovered that the stone slabs on the ground were all Rong Yang Stones.

This stone is a kind of supreme yang object of time, and it is naturally extremely harmful to ghosts.

The hall was not small, but it was very empty. Besides a half-height stone platform in the center of the room, there was nothing else.

Wang Yu walked forward and looked at the stone platform.

He saw that the square stone platform was engraved with various complex patterns that extended to the Rong Yang Stone floor. In the center was a circular recess, which contained a white circular stone disc.

The stone disc was placed at an angle, and the edges were engraved with marks indicating the twelve Earthly Branches, such as Zi, Chou, Yin, and Mao. In the center stood a half-foot-long black iron needle, which was actually a sundial.

A blue light flashed in Wang Yu's eyes, and he checked the sundial. He saw a faint gleam flowing on it, like a clear spring under the moon, rippling with silver light.

After watching for a while and seeing nothing strange, he raised his palm and touched the sundial.

As a result, just as his hand reached into the recess and before he touched the stone disc, an unexpected change occurred!