Elf: I have a secret realm of emerald green.

However, there are no longer any naturally formed ultimate caves in the secret realm.

If it doesn't have the ability to open the ultimate pore, theoretically it has no possibility of returning home.

Xia Shen felt that the most likely scenario was that after searching for the Ultimate Cave in the sky to no avail, they would return to the ground, gather energy, and wait for the next journey.

However, what awaits it is only the next cycle of reincarnation.

Yan Yan nodded, then asked, "However, according to you, most Ultra Beasts are very dangerous beings. When we go out this time, we should tell Lilif and the Secret Realm Research Institute about Ultra Beasts, right?"

“I will definitely say it, but I don’t know if they will listen.”

This thing is similar to the spirit world; if they don't see Tetsuka Kaguya with their own eyes, it's hard to verify this.

"Then how did you know all this?" Yan Yan asked, then suddenly waved her hand and added, "Ah, it's okay if you don't want to tell me."

Xia Shen was helpless; it was yet another century-old problem.

He was faced with two answers...

[I came from another time] and [what Kexi told me]

He didn't want to deceive Yan Yan, but telling his girlfriend the truth... seemed too strange.

…………

Seemingly sensing Xia Shen's predicament, Yan Yan smiled gently and took the initiative to change the subject.

"By the way, what's the situation with those ruins?"

Xia Shen took a sip of water and said, "I really don't know, but I'm planning to go for a walk around those ruins this afternoon. Do you want to come with me?"

Although he asked about Yan Yan and all the Pokémon, Xia Shen clearly did not have any diving suits for Garchomp and Ursaring.

Even if they wanted to go, they couldn't; they could only stay obediently in their Poké Balls.

As the daughter of a famous explorer of secret realms, Yan Yan naturally wouldn't miss such an interesting opportunity.

The remains of human civilization in a hidden realm... If this discovery were reported, it would definitely be a sensational news story that would shake the world.

So the two agreed to return to the seabed after lunch.

"But what about these Mertans? They seem to need you."

Yan Yan looked at the little trinkets on Xia Shen's body and chuckled jokingly.

Xia Shen shook his clothes and found that they were still clinging to him tightly, refusing to let go. He sighed helplessly.

"Maybe the shock you experienced earlier was too great... You know the suspension bridge effect, right? It'll be fine once things calm down."

To be honest, Xia Shen's purpose in coming here this time was simply to visit Meilutan's relatives.

As for any superfluous thoughts, such as releasing his own Meltan or subduing all Meltans, he had none of them.

He was even somewhat reluctant to let Meltan evolve into Melmetta.

Meltan is so cute, it's tiny! As for Melmetta...

There are already enough giant Pokémon in the team, and Meltan has never shown any interest in Pokémon battles, so there's no need for it.

Of course, if Meltan wanted to evolve on its own, Xia Shen would never stop it.

But it's not good to keep these few Mertans hanging on me all the time.

Left with no other choice, Xia Shen had to call over his pet Melutan to persuade his companion.

A moment later, Xia Shen finally unloaded the burden on his shoulders.

But looking at the strange looks the Meltans gave him, Xia Shen didn't know what the Meltans had said to them. He hoped it wasn't anything weird.

…………

There were many more elves at lunch today. Many of them, having tasted the sweetness of human civilization, came over to freeload.

Of course, they also picked a lot of fruit from the trees in exchange.

Having stockpiled almost two months' worth of food, Xia Shen welcomed all who came and generously treated all the elves of Chanchan Hill to a feast.

It turns out that the ability to foster friendships at the dinner table applies not only to human societies but also to elven societies.

After lunch, Xia Shen could basically declare that the Murmuring Hill had taken on its own shape.

The overlord spider, having seen Xia Shen and Tapu Lele standing together before, also held Xia Shen in high esteem.

To some extent, it can be considered a disguised form of borrowing someone else's power.

After lunch and a short rest, and after taking care of some matters at home, Xia Shen and Yan Yan embarked on their journey to explore the lost civilization.

This is because, combined, only Grimtar and Milotic can fight in water.

Xia Shen even borrowed a high-level professional Spider King from the Spider King leader to act as a bodyguard.

Although there shouldn't be any danger in that building ruin, it's always best to be fully prepared.

Leaving the Meltans behind on the babbling hill, Xia Shen and Yan Yan changed back into their diving suits and rode the Dark Tail Black Fish and Milotic respectively, diving into the lake.

Having already made the trip there once in the morning, the Dark Tail Fish easily found the ruins.

Yan Yan's physical condition was far inferior to Xia Shen's, and he couldn't carry a heavy oxygen tank. So after surfacing to change the oxygen tank, they dived back into the sea.

Also due to oxygen limitations, the first exploration only lasted one hour.

…………

Finding a door in ruins is no easy task, let alone when those ruins are in the sea.

Although the Tetsuka Yamata ignited and took off, it had already "sweeped away" a large part of the silt covering the complex, most of the ruins were still hidden in the sea mud.

If it weren't for the unexpected incident involving Tetsuka Kaguya, this unknown civilization might have remained buried for who knows how long.

After circling the ruins for almost a full time, Xia Shen found many doors, but the thick steel plates made him not even consider breaking them down.

Needless to say, the walls that appear to be supported by reinforced concrete are even more so.

It wasn't until he used his mental powers to probe that Xia Shen discovered something that resembled a window.

Let the black fish with a water gun wipe away the mud on the surface, and you'll see that the glass, though weathered by time, remains brand new and transparent.

Glass takes a million years to degrade naturally, so this civilization must have existed for at least a million years.

The information deduced seemed useless, so Xia Shen stopped thinking about it and instructed the three Pokémon to use their moves on the glass.

Milotic and Dribou fired four or five water cannons in succession, and the Dark Tail Blackfish's wave attack almost smashed its head before the glass finally showed a few cracks.

Xia Shen concluded that this was definitely tempered or reinforced glass.

But once a crack appears in the glass, it means that breaking it is not difficult.

After another barrage of attacks, finally, with a water cannon shot from Dr. Spider, a large hole was finally torn in the huge glass curtain wall.

They turned on the emergency lights they had prepared beforehand and carefully crawled into the hole filled with shards of glass.

Just like the Peach Blossom Spring described in the story, it was initially extremely narrow, barely wide enough for one person to pass through. After walking several dozen steps, a bright and open scene appeared before Xia Shen and Yan Yan.

…………

Xia Shen had to thank the door and wall that had just prevented him from entering; the solid barrier not only kept them out but also blocked the erosion of time.

The items inside the room were certainly not brand new, but at least their general appearance could still be discerned.

Tables and chairs soaked beyond recognition by seawater, and precision electronic instruments of unknown purpose...

Xia Shen and Yan Yan exchanged a surprised glance. This seemed to be a research institute?

Since it's an elf secret realm, it's also very likely an elf research institute.

Could it really be the Ether Paradise?

I glanced at Yan Yan's oxygen tube; there was still a little over half left, which should be enough to explore the entire room.

Releasing his mental energy once more, Xia Shen carefully searched the research institute that resembled the Ether Paradise.

As he swept his gaze across the corner, the contents of a tightly sealed iron box startled Xia Shen.

……

A basic physics lesson from middle school tells us that water and oxygen are two of the main factors that cause iron to rust.

The electrolytes in salt water make iron more susceptible to electrochemical corrosion.

There is no doubt that seawater meets all of the above characteristics.

But strangely, the surface of this iron box... no, it should be said that it was an unknown metal box, was incredibly smooth, without a trace of corrosion.

This metal box alone must be quite valuable, right?

Of course, Xia Shen, who was well-versed in fables and understood the principle of buying the box and returning the pearl, valued the contents of the box even more.

He tried to use his mental power to pass through the unknown metal, but failed. This did not make Xia Shen feel frustrated; instead, it made him even more curious about the items inside.

With a thought, the box in front of him vanished from this space.

Clearly, no matter how strange the substance, it cannot withstand the power of Arceus, the creator god.

Yan Yan was already immune to Xia Shen's various strange behaviors, and she wasn't surprised at all by his magic trick.

Next to the box, Xia Shen easily found a key made of the same material.

Without a doubt, this equally impervious object is the key that comes with the box.

The two men, carrying flashlights, continued searching the room for other items.

Although the room was not small, most of the items, like the electronic equipment, were corroded beyond recognition.

Seeing that there was nothing else of value and that the oxygen supply was running low, Xia Shen and Yan Yan returned to the surface of the sea.

First, we need to change the oxygen supply; second, we need to investigate that mysterious metal box.

Just above these ruins was a small island, smaller than Xia Shen's own house, but big enough for Xia Shen and Yan Yan to rest and stay.

Using the old trick of building a good relationship with the long-winged gulls using energy cubes, the two set up a simple tent in an open space.

This civilization's remains are vast, and it's impossible to explore them all in a short time. At least we have a place to rest temporarily.

…………

After resting in the tent for a while, Xia Shen summoned the metal box.

The box was quite large, square in shape. Xia Shen estimated its size to be about one cubic meter.