For survivalists, challenging all kinds of extreme environments is their favorite. It is not a simple "death" as it is said, but ordinary trivialities are difficult to threaten them, as long as the extreme environment can provide them with experience.

Of course, the same is true for Bufan, this kind of thing is really a piece of cake for him.

When he was studying in Prussia, he often visited extreme terrain such as sinkholes, and compared to those sinkholes that were at least hundreds of meters deep, the underground cavities in front of him were obviously completely incomparable.

The chain guide clicked continuously, the chain rappelled quickly, quickly and steadily descended to the solid rocky surface, and stood firm, the first thing Bufan did was to quickly scan the surrounding environment with an emergency light.

The first thing that catches the eye is the reflection from all directions, and Bufan is not surprised by this - it is obvious that it belongs to the limestone dissolution terrain, which is characterized by a large number of associated crystals in addition to the stone cones, stalagmites, and stone milk formed by the dissolution and solidification of various limestones, such as the most common semi-permeable calcite and quartz, as well as fluoride fluorite, beryl, etc., and even sometimes various metal ore crystals.

The cavity is very quiet, there is occasionally a trace of distant wind and dripping sound, other than that, there is no other movement, and the air here is even fresher than the interior of the original civil air defense project above, not so strong rotten smell, but more faint sulfur smell.

There were ventilated holes, and more importantly, there would never be snakes, and with these two conclusions, Bufan's stagnant and vigilant figure finally relaxed, and began to scan all the details around him with the help of emergency lights.

This underground cavity is not very large, the whole presents a slightly flattened irregular olive shape, the long diameter of the "olive" is about forty or fifty meters, and the short diameter is also twenty or thirty meters, from the ground of the stone lotus stalagmite everywhere to the slightly sleek dome, it will never exceed twenty meters, and the highest point of the dome happens to be the collapse of the ground of the civil air defense project that was dug a hole by Bufan, it is obvious that as long as there is no strong external force in this structure, there will never be the danger of collapse!

Gone, Bufan's previous fear of collapse had vanished, and his interest in exploring such places had increased.

It is clear that this is a typical northern limestone cave.

Unlike the south, where there is plenty of water, the caves in the north are mostly dry, and there are no fungi such as mosses on the ground, and there are few wild species such as bats, without which the cave floor would not have formed a humus layer of soil, and thus would not have formed an ecosystem like the southern caves.

Rather than the damp, mostly foul-smelling southern caverns of all kinds, Bouvan clearly prefers the one in his hometown, an unfortunate underground space that could be used for the future — he had no idea of using it as a public tourist space.

Looking around, you can see a variety of limestone associated crystal clusters, shining brightly under the illumination of emergency lights.

Bufan crouched down, looked closely, and easily identified that it was the most common calcite, not some magnificent gemstone or something, and then walked around, and found that there was no additional damage to the crystal clusters except for a few broken crystals caused by the stone he had chiseled down earlier, and he came to the conclusion that this was a place that had not yet been visited by humans.

The "olive" cavity is not an isolated one, and in several different directions, pathways can be seen in different directions, some of which are enough for Boufan to bend over, and some are the size of a football.

Bufan listened quietly at every accessible intersection, but he did not test it at will—audacity is sometimes the cloak of ignorance, and prudence is the best crutch to walk in all directions.

It was already the second half of the night, and there was still something going on during the day, so he couldn't stay here for long, and most importantly, he wasn't well prepared.

However, just going back empty-handed after just coming down, Bu Fan always felt a little unwilling in his heart.

His eyes swept over the crystal reflections that could be seen everywhere, and he had an idea in his heart - it would be good to bring some crystal clusters back and give them to his father at home as a table decoration, after all, it is almost the lunar month, and the Spring Festival is not far away.

Because of his perennial exercise, Bufan's energy can be said to be very abundant, and he doesn't care about the time or anything like that, so he walks around in this fairly open cave.

There are a lot of calcite crystals clustered on the ground, but most of them are not very long, and they can be seven or eight centimeters long, which is already good. This is very common, and the rainfall is scarce in the north, and the groundwater is also not abundant enough, and the scarcity of groundwater directly affects the quality of crystal formation.

Bufan was looking for something special, the lamellar structure of calcite was too easy to break.

One and a half meters tall stalagmites are boring, stone lotuses with a diameter of two meters can't be dug up, and three or five clusters grow... Oh, it's calcite again, it's too common, and it's easy to dig up, and the fine yellowish crystals, well, this one should be crystal, but it's too small to be a tabletop ornament......

Turning around, in a slightly higher stone lotus, Bu Fan saw something different.

This stone lotus is not large, at most half a meter in diameter, which is relatively small in this underground cavity.

Under the cold light of the emergency light, Shilian and the surrounding ground are a little bleak gray-white, gray-white is very uniform, which can prove that the composition of Shilian is limestone, according to common sense, if there are crystals in the middle of Shilian, most of them are semi-permeable calcite, at most there will be some transparent quartz.

However, what Bufan saw was different, there was a circle of regular clusters of crystals, and the center of the crystal was a multi-faceted prism crystal, this shape was not unusual, the key was that the clustered crystals were a little purple, but the multi-faceted prism in the center was very crystal golden, and the two colors were put together, and the yellow prism in the middle was as dazzling as a small sun.

Purple, amethyst, golden yellow, pyrite?

Without the instruments at hand, Bufan couldn't tell with certainty, but with the eyes of the world he had once walked, he could conclude that this crystal combination was a good natural work of art, at least it would be absolutely appropriate to make a gift for his father, who likes to collect ores.

So, there was only one thought left in his mind, to dig this thing up and bring it back!

It is unrealistic to chisel this crystal combination alone, most of the crystals cannot withstand the force of sharp or blunt objects, and the same is true for the "sun" crystal cluster in front of you.

But fortunately, there is a stone lotus wrapped under this group of crystal clusters, maybe the entire stone lotus can be chiseled down together with the crystal clusters, and the complete stone lotus can just happen to be used as the base support of the ornament?

The only labor-saving power tool wind drill is used for violent excavation, and it is obviously not suitable to get Shilian down completely.

Bufan took off his gloves and reached out to feel the junction between the stone lotus and the stone platform below, where there was a not-so-obvious depression band, and he removed the planing root and the small T-pickaxe from behind his waist, oh, and a short chisel pinned to the tool belt, and clanked it.

The root planing is a kind of chisel hammer similar to an axe, but different from the cutting edge of the axe, the cutting edge of the root planing is horizontal, the cutting edge of this tool is not sharp, in the soil work, it is especially suitable for digging fossils that may exist in the layers of sedimentary rock, and it is not suitable for breaking hard limestone...... Obviously, this thing is not suitable for opening a crack between the stone lotus and the rocky ground.

Therefore, if you want to achieve your wish, there is only one way in a short time - a hammer head for digging roots with a hard chisel, and a little bit of manual operation is done slowly, which requires patience and skill instead of strength.

Fortunately, no matter which one it is, Bufan is not lacking.

Half-squatting down, clanging circles and chiseling, about half an hour, a crack began to appear under the stone lotus, Bu Fan's strength was still there, but the sweat caused by physical exertion was difficult to control.

Anyway, he worked slowly and carefully, and there wouldn't be many stone chips, so he took off the safety helmet on his head......

There are still gaps between the stone lotus and the stone layer below, which are not originally one, but still have some gaps...... Just when everything felt in order, when Bouvan felt that he could achieve what he wanted with a few more chisels, the unexpected happened.

The "sun" crystal cluster jumped up inexplicably.

"Bang", right in Bufan's forehead.

"Damn!" Bufan, who was doing things alone, scolded casually, and then fell to the ground, and after a while, he felt wrong, not the kind of drowsiness that was smashed, but something damn desperately drilling into his forehead!

The heart-rending pain may not be as good as this feeling, and Bufan only has such a realization left in his heart, and he can't even shout.

As for his movements, he was no longer restrained at all, and he began to roll around in excruciating pain, and the clusters of crystals around him were like thorns and like short swords cutting through his clothes...... and skin.

However, in such a confined space nearly thirty meters underground, who could find out what was wrong with him?

Tossing and rolling, Bufan inadvertently grabbed the T-shaped pickaxe that he had thrown aside earlier, and he couldn't break his head even if he was still conscious, so he could only hold the pickaxe tightly, curse "Damn!" in a deep voice, and then fainted.

Except for the remaining lights, there was no concept of time underground, and I don't know how long it took, and after a burst of gold and purple flashes, Buvan, who fainted to the ground, suddenly disappeared.