Transmigrated into a book? A vicious female supporting character? A senior sister? Tsk tsk!

Yun Xingnan smiled approvingly and continued:

"I suspect the 'key' is with the Mermaid Knight. If we don't understand it and try to break it using ordinary formations, once the 'lock' here is broken..."

The 'key' from the Mermaid's side will immediately disappear, that's one issue. The second issue is the restoration of the formation.

This kind of mother-and-child concealment array is easy to set up, but the key is that it must match the 'key' in the hands of the merfolk riders; otherwise, the next time they come, they'll find that someone has already been here.

Gu Moxu couldn't help but exclaim in amazement:

"It's so complicated!"

Lu Chuan'an smiled and said with considerable confidence:

"It's not really complicated, just a bit tricky."

Yun Xingnan hummed in agreement:

"Indeed, this thing is nothing to the senior."

Seeing that the two were both confident, Gu Moxu hurriedly urged them on:

"Then hurry up, brother, lest that shark rider suddenly comes over again."

Tang Xinyan rolled her eyes:

"Fourth Brother, don't go on and on. Don't you know that people can't stand being talked about? If you do, they'll throw you out."

Gu Moxu looked pitiful:

"Little sister, you're too heartless. Is this what you call using and discarding?"

Tang Xinyan: "Hehe."

Gu Moxu wanted to say something more, but seeing Yun Xingnan begin to channel spiritual energy into the formation, he immediately shut up, afraid of disturbing him.

A moment later, the array on the stone wall appeared, and indeed there were many gaps, like a maze map with parts of the route erased.

To ensure everything went smoothly, Yun Xingnan took out a recording stone and carefully recorded the emerging formation. Then, he quickly formed hand seals.

A short while later, an array that was the same shape and size as the one on the stone wall, but with the exact opposite pattern, appeared in Yun Xingnan's hand.

While Tang Xinyan marveled at the wonder of it, she was also somewhat uneasy:

"Brother, if we break this formation this way, will the key from the Mermaid Knights' side not disappear?"

Yun Xingnan hummed in agreement and explained:

"No, this is a flaw in this kind of formation. You can think of it as a lock with multiple keys. As long as the lock is not forcibly destroyed, the keys will not disappear."

With this analogy, Tang Xinyan instantly understood and said no more. Seeing that she understood, Yun Xingnan no longer hesitated.

He slowly pushed the array in his hand toward the array on the stone wall. The two arrays matched each other, and a flash of light appeared as the two merged into one.

The complete array slowly disappeared, revealing the mechanisms and buttons on the stone wall. Yun Xingnan then used his divine sense and spiritual power to carefully examine them.

After confirming that there were no other hidden tricks, Yun Xingnan pressed the button. Accompanied by the sound of stones rubbing together, the stone wall next to the bookshelf slowly opened from the middle to both sides.

The space inside wasn't large, and the stone walls had likely been specially treated, making the interior pitch black; even with night vision, it was impossible to see anything clearly.

Only by relying on two pieces of fluorite embedded in the stone wall can one vaguely see the general outline of the stone chamber, and on the innermost stone wall, one can vaguely see a person hanging.

Fearing there might be some hidden traps or weapons inside, Yun Xingnan first used his divine sense to slowly probe inside. After confirming that it was "clean," he then checked the people on the walls.

However, when he saw the other party's situation clearly, Yun Xingnan felt a bit emotional. He could roughly determine that this person was Jiao Shiqi.

Although he had never witnessed how spirited and ambitious Shi Qi was when he became the Mermaid King, he was probably quite impressive.

But now, his meridians are broken, his cultivation is completely lost, most of his scales have fallen off, his skin is dry and wrinkled, and he no longer looks like a human being.

If it weren't for the slight rise and fall of his chest, Yun Xingnan would have thought that what was hanging inside wasn't a living person, but a desiccated corpse.

Yun Xingnan withdrew his divine sense and explained the situation inside to Tang Xinyan in detail, then asked:

"Little sister, what are you planning to do?"

Before coming, Tang Xinyan had already come up with two plans. The first plan was to use underhanded tactics, since this kind of tough nut might not be swayed by either soft or hard approaches.

It's better to play dirty tricks, knock the other person unconscious, feed them a Mantra Pill, or if that doesn't work, use Soul Search, but that would be very troublesome if successful.

As for Plan Two, it involves disguising oneself as Lingxi to see if the truth can be extracted. However, this is easily exposed, and might even backfire.

Therefore, Tang Xinyan prefers Plan One, and can always deal with whatever comes her way if necessary.

But after hearing Yun Xingnan's description, Tang Xinyan actually felt that Plan Two was not bad. The other party was in such a miserable state that even the most hard-hearted person...

She figured that when she occasionally reminisced, she would inevitably feel regret, and she could use that to her advantage. So she said to Yun Xingnan and the other two:

"Big brother, second brother, fourth brother, you all stay out here and keep watch. I'll disguise myself as Lingxi and go in alone."

Although all three were somewhat uneasy, they all knew that their junior sister was a shrewd and capable woman, and ultimately they all agreed.

Tang Xinyan took out the Phoenix Clan Disguise Pill that Lingxi had given her, ate it, and transformed into Lingxi's appearance. She then inserted Lingxi's feathers into her hair.

In this way, both his aura and appearance are identical to Lingxi's. Although Jiao Shiqi has lost all his cultivation, Tang Xinyan felt it was best to be cautious.

Fortunately, when she and Lingxi discussed this privately, she had vaguely come up with such a plan, so she asked Lingxi to give her a few Phoenix Clan disguise pills.

Tang Xinyan took out a luminous pearl and deliberately imitated Lingxi's posture and expression, slowly walking into the stone chamber. As the door to the stone chamber closed,

In the dimly lit stone chamber, the luminous pearl in Tang Xinyan's hand was particularly conspicuous. Perhaps sensing the light, the merman Shiqi's lowered head moved slightly.

However, he did not lift his head, but spoke in a hoarse, slightly panting voice:

"Jiao Bing? Don't... waste your energy... I... won't tell you... just... die, give up on that idea."

Tang Xinyan conjured up Lingxi's voice, gave a light sneer, and said gloatingly:

"Hahaha, I never expected this, Jiao Shiqi, you've finally met your match!"

Jiao Shiqi stiffened for a moment, but quickly followed with a light scoff, saying disdainfully:

"Jiao Bing? You... could it be that you've lost your mind and are actually trying to use this trick to fool me?"

Tang Xinyan sneered, her tone harsh and sarcastic:

"Oh? Someone actually used my identity to deceive you? That's really foolish. After all, you only use me. We're sworn enemies."

These words silenced Jiao Shiqi. Just as Tang Xinyan was pondering whether to continue provoking him, he seemed to remember something and slowly raised his head with great effort.