Tan Chu and a group of players were puzzled by these useless black liquids that the mechanics had solemnly collected.

The system has made it clear that these black glues are just the residue left over from refining black oil and have no other valuable functions.

In other words, these are the garbage left over from refining fire oil, which can be thrown away...

But the mechanic players spent a lot of gold to buy this kind of metal storage box, and kept the garbage so well...

"Boss, you may think that these things are not of much use, but don't be fooled by the introduction of the system, these black glue that looks like garbage have a magical function." Fei explained with a smile.

"Oh, tell me, what's the use of this kind of thing?" Tan Chu asked with a smile.

"After refining the black oil oil, we were pleasantly surprised to find that a barrel of oil can refine three kinds of props, one of which is blazing crude oil, which is the most important refining prop, and the second is a black crystal block, this material is a small energy crystal, just like the boss's ink crystal spirit source, but the energy is less than one percent, which is not very practical, and the last one is this black glue." Xiaofei said.

"Then you say, the black glue even gives a waste evaluation to the system, what is the reason why you keep it so well?" Zhang Daishan asked curiously.

"Miss Zhang, according to the introduction of the system, this black glue is a kind of waste residue, we were going to throw these things away directly, but by chance we found that this glue actually has a very strong adhesion, once it gets on our hands or limbs, it will stick to it and can't get out, until the system is updated, we can regain our freedom." Xiaofei said.

What the?

Adhesion... Tan Chu and the others were puzzled...

"The so-called adhesion means that once these glues get on our body, they will stick to it, and it is impossible to shake it off, especially if they stick to the hands and feet, then there is no way to separate them at all." Xiao Fei saw everyone's doubts, so he explained in detail.

"Are you saying that as long as this black oil touches our hands, our fingers will not be able to open, and when they touch our arms and bodies, we will no longer be able to move freely?" Tan Chu asked in surprise.

"Yes boss, you're right, this kind of thing can stick all props except metal, and they can't be separated as long as they are glued." Fei replied.

"No wonder you use metal boxes to preserve these glues, it turns out that for this reason, it is well done, it is indeed a good thing!" Tan Chu said excitedly.

After listening to Xiaofei's introduction, he understood very well that the waste scum identified by this system is a kind of magical treasure for players...

Even if it can't make anything, it's a powerful offensive item due to its sticky properties!

Especially in the upcoming siege battle, if there are countless such black glue on the city tower, all of them will fall towards the evil soldiers below the city tower...

It must have been spectacular!

"Boss, this black glue is extremely prolific, so... There are quite a few piles here. Fei said.

"Xiaofei, these black glues can't be wasted at all, all of them are kept for me in a metal box, I have a lot of use." Tan Chu immediately said with a smile.

I didn't expect the garbage identified by the system to be a treasure!

"No problem, don't worry, boss, we won't throw these things away." Xiao Fei laughed.

"Okay, I don't have to worry about your ability to do things, within three days, you have to produce as many of these props as possible, and then we will be more sure of defending the city." Tan Chu advised.

"Understood, boss." Xiao Fei was praised and immediately replied excitedly.

"Then you guys hurry up and get busy, time is tight." Tan Chu said.

He didn't want to waste Xiao Fei's precious time, and he didn't look at the third black spar, so he directly asked this newly acquired right-hand man to immediately command the mechanic players to step up their efforts to collect and refine the black fire oil...

Watching Xiao Fei leave quickly, Tan Chu left the warehouse with a group of players and went to the city tower to watch the current situation of the entire Shadow City...

"Mr. Shi, can this place be raised to the scale of a city in three days?" Tan Chu stood on the city tower, looking at the system buildings that were being upgraded everywhere, and couldn't help but feel a little worried in his heart.

If it is only according to the materials needed for urban upgrades, the Shadow Legion is ready, but the cooldown time required for building upgrades makes Tan Chu feel a little headache...

Every building in the city now has rows of numbers on it, representing the cooldown time of the upgrade.

Tan Chu, who has expanded the Beast Against the Sky City, understands very well that this kind of waiting is very helpless, but he can't spend gold coins to speed up time like in previous games...

"Boss, let's just watch the things in the city, you better continue to level up and improve your strength, you can't delay your leveling event because of the situation here." Shi Qiusheng persuaded.

"Yes, Boss Tan, my brother and I can just watch it here, you better go with the Beast Alliance to farm monsters." Shi Qiutong followed.

"Okay, you guys bother, I'll go to the dwarves tomorrow for help." Tan Chu nodded and said.

He immediately walked down from the city tower with a few beautiful women, rode out of the city gate on his mount, and continued to find the legion team led by the Dark Night Cangfeng, and upgraded together...

Back in the swamp altar area, Tan Chu and the beauties joined the legion, and while following these players who were not prestigious, they continued to farm monsters, while racking their brains to think of all the means to defend the city.

The Spirit Clan's Spirit Death Elder, the gift of the Green Vine Spirit Seed, can deal with the large groups of soldiers of the Demon Clan...

The burning power of blazing crude oil can also deal a lot of damage to the Hive Legion...

But the biggest surprise is the discovery of black glue!

This strange thing is systematically identified as the waste residue produced by the refining of black oil oil, but it has extremely strong adhesion...

Tan Chu immediately thought of a way to use this glue to deal with the evil clan legion.

The most critical problem now is that the quantity of this material is still too small, so Tan Chu promised a heavy reward and encouraged the mechanics to hurry up and strive to collect and refine as much black oil as possible within three days...

Although he knew very well that this precious blazing crude oil was a bit wasteful for the defense of the city, the current situation had made him careless.

Thinking about the problem in his heart, Tan Chu followed the team of players of the Beast Alliance, leading a large number of evil soldiers in the altar area, constantly brushing up on reputation and experience...

The day passed quickly, and in the middle of the night, Tan Chu went to see the expansion progress of Shadow City before going offline...

The current town, after a day of continuous upgrading of buildings, has reached the standard of a third-level town, and it should be able to be upgraded in the middle of the night.

It doesn't take much time to get from a first-tier town to a second-tier town, but if you upgrade from a second-level town to a third-level town, the cooldown time will be doubled...

After all, there are a lot more buildings in the city after the upgrade, and the next city expansion order will only be opened after each building is upgraded to the level required by the system.