After Su Yuan finished placing the hangup, he ignored it and looked at other columns of the exchange, wanting to try whether he could buy some useful things.

Not to mention, he really discovered something.

"The design drawing of the advanced water filter is only replaced with 50ml of water!"

A line of titles emerged.

Su Yuan showed surprise.

Advanced water filter?

This should be much better than the simple water purifier given in the system, right?

Su Yuan directly clicks on the transaction.

【bite!】

【Design drawing of advanced water filter +1】

Su Yuan took out the design drawings directly and observed them.

[Design drawings of advanced water filters: stones (0/2), fabrics (0/2), fine sand (0/2), ordinary runes (0/2)]

[Advanced water filter, extremely efficient water filter, can filter at least 3000ml of water resources a day.]

Su Yuan suddenly thought in his heart.

Need runes to design?

Are some things that are not in the system? All runes are needed to be designed.

The same goes for waterwheels!

But now he only has an ordinary rune left, so he can only keep this design drawing first.

Su Yuan continued to watch the scene in other columns.

In the end, he exchanged some gauze, alcohol, and anti-inflammatory drugs.

Whether it is useful or not, save it in advance, there will be no mistakes.

Make sure there is nothing else to change for the time being, and he then retreated.

Su Yuan then clicked on the [Life Items] manufacturing again, and at the cost of four woods, he created four buckets.

He smiled and walked out of the room, called the skeleton soldiers, handed it two buckets directly, and issued an order to get water into the lake three hundred meters away.

Anyway, the skeleton soldiers are covered with skeletons, and even if they really encounter black water leeches, they will not be damaged at all.

After the skeleton soldier left, Su Yuan immediately made a simple water purifier.

【Simple water purifier: wood (0/2), stone (0/4), gauze (0/2), fine sand (0/3), black activated carbon (0/3)]

…

The entire water purifier is more than half a person tall, and looks like two buckets stacked together.

At the bottom, a faucet-like leak is specially used to filter clear water sources.

The more Su Yuan looked at him, the more satisfied he became.

Soon after, the skeleton soldier walked over from the darkness in the distance with two large buckets of water.

Su Yuan controlled the banshee owl as soon as possible, and the paralyzed ghost bee quickly surrounded him. After carefully checking the water source and the skeleton soldiers to ensure that there were no black water leeches, he was relieved to let the skeleton soldiers approach and poured the two buckets of water into the water purifier.

Tick, tick…

The leaking nozzle under the water purifier quickly began to slowly drip out of clear liquid.

Su Yuan was delighted when he saw it.

"efficient!"

He hurriedly moved a clean empty bucket under the leaking mouth and began to collect water resources.

After doing all this, Su Yuan came outside the room again, looked at the guards who were digging the pond, and continued to give them an order, asking them to start digging the canal after they dug the pond.

After Su Yuan gave the order, he closed the door, took out the secret book of the [Golden Bell Cover], and looked in the room.

Now, taking advantage of the crisis that has not yet arrived, it is the best way to improve your strength as soon as possible.

Time passes by bit by bit.

It was from 10:30 in the morning to 6:00 in the evening.

During this period, Su Yuan got up and ate a white bread, drank half a bottle of water, and ate a handful of black spirit fruit.

It took me half a day to finally get the secret book of this [Golden Bell Cover].

…

Name: Su Yuan

Age: 18

Room runes: Normal runes (3 pieces), earth-attribute runes (2 pieces)

Room special effects: Level 1 gravity field (0/4)

Room safety: One star (0/6) (Your room is safe, but don’t be proud. It is still one of the lowest-level rooms. Please upgrade to two stars as soon as possible.)

Room Guardians: Red-clothed Evil Spirit (1), Paralyzing Ghost Bee (7), Skeleton Soldier (1), Mutant Banshee Owl Soul (1), Mutant Rotten Knight Soul (1).

Room area: 50 square meters

Personal skills: Dead Wood Art Entering the Hall (1/5), Golden Bell Cover Introduction (0/2)

Personal Strength: Dark Apprenticeship Later

…

In general, my personal strength has not changed, but I have one more skill.

As he expected, the Golden Bell Cover also needs runes to upgrade.

Su Yuan looked at the skin of his arm and suddenly tensed. He saw thick blood vessels suddenly appearing on the skin. The skin color quickly turned yellow at a speed visible to the naked eye, as if he was coated with a light golden paint.

"Sure enough, like the ones who performed in the TV series, will they become the Eighteen Bronze Man if they continue to practice like this?"

But even if the image is a little bad, it's okay, as long as it can save your life.

Su Yuan suddenly thought of another question.

How many times can this secret be traded?

Can't it be unlimited trading?

That would be too buggy.

He got up from the bed and came outside the yard again.

The pool in the yard had been completely dug, ranging in size seven or eight meters and three or four meters deep. After digging the pool, the three guards dug out a long canal with shovels, leading to the darkness in the distance.

Su Yuan carefully closed the door and followed him immediately with seven paralyzed ghost bees and banshee owls.

Soon after, I saw the evil spirits in red who were working hard to dig the canal more than 200 meters outside the yard.

This place is only a few dozen meters away from that lake.

The more Su Yuan looked at him, the more satisfied he became.

Although there are only three guards working, the efficiency of this working is at least thirty people.

He controlled the Banshee Owl and circled towards the lake again.

[There is a Black Water King hidden deep in the lake in front of you. Not far from it, there is a copper treasure chest!]

[You'd better get that copper treasure chest quietly, with surprises inside]

Two lines of prompt text suddenly appeared.

Su Yuan's face was stunned.

Is there a copper treasure chest in the water?

After searching until now, I have never encountered a copper treasure chest!

Just by listening to the name, you will know that it is definitely much more advanced than ordinary wooden boxes.

In an instant, a trace of light appeared in Su Yuan's eyes.

He first controlled the Banshee Owl and quickly swooped into the black lake.

The body of the Banshee Owl once again turned into an illusory state and pounced on him.

Countless black lees in the lake rushed out and rushed towards the banshee owl's body, but they all passed through its body.

The Banshee Owl soon arrived at the bottom of the lake.

After entering the bottom of the lake, its sight was obviously blocked.

The originally 80 meters of force now has become about 30 to 40 meters.

Moreover, there are more lees in the water, densely packed, forming a group of black shadows in the lake, greatly blocking its sight.

Fortunately, the body of the banshee owl turned into illusion and quickly passed through these groups of black water lees.

After some searching, Su Yuan finally found a treasure chest with copper light on the right side of the lake bottom.

He immediately controlled the banshee owl to dive, his claws solidified, and grabbed the copper treasure chest hard.

Just as the Banshee Owl grabbed the copper treasure chest, a huge tentacle suddenly rushed out of the mud at the bottom of the lake, wrapped the claws of the Banshee Owl in an instant, and pulled it hard into the mud at the bottom of the lake.

Such a scene changed Su Yuan's face.

At the critical moment, he once again turned the Banshee Owl into an illusory state and quickly escaped from the entanglement of the tentacles.

I saw the ground at the bottom of the lake surging, and a huge black lee suddenly rushed out of the bottom of the lake, and its body was flat and spread out, like a huge round carpet, with a radius of more than three meters, and it was black and extremely terrifying.

Su Yuan was dumbfounded.
Chapter completed!