The Witcher: Son of the Planes.

While Rose was preparing supplies, Colin spent a few comfortable days.

In the end, it was not known whether it was because Rose was a little slow in preparing supplies or because Colin couldn't hold on, but Colin, feeling a little tired, had to set off a few days earlier than originally planned.

The journey was uneventful, as it was still a familiar road. After passing the entrance to the town outside the college, Colin entered the underground world again.

The underground world was still the same, still dark, damp, and cold, the light was very weak, and visibility was very low, but Colin, whose mental strength had greatly increased, could see farther.

The aura of a first-level creature is not something that ordinary creatures can resist. In the past, the so-called "guides" who would surround people as soon as they saw them did not dare to step forward to disturb Colin, a big shot.

It turns out that some of these "guides" also work as part-time thieves. When they see a fat sheep coming their way, they will kill the employer in a place with few people around, and then dump him in a remote place to make sure no one knows.

But today, these "guides" were silent and did not dare to come forward and make any noise, for fear of accidentally angering Colin and encountering something unexpected.

You have to know that the underground world is synonymous with chaos. Although there is the rule of the underground holy tower, there are always places that the holy tower cannot reach, especially the underground indigenous people are more vicious and cunning than the humans in the surface world.

Colin, who was familiar with the route, didn't pay attention to the guides in the distance and quickly rushed to the city of Vatna.

The familiar scenes on the road reminded him of the underground elf Akona, but it was just a thought. Although her body proportions were good, she was not his type.

After releasing Charles, Colin stood on Charles' back and directed Charles to fly forward. Charles, who came underground for the first time, was still a little uncomfortable and always felt that there were hidden dangers in the dim environment.

But Colin knew that it was not the case, it was just Charles' illusion. With Charles' help, traveling was no longer a difficult task.

Last time, Colin and Akona walked on land, but this time they flew in the air, which was a different feeling. However, there was nothing more to it, as the dim environment still affected people's good mood.

Half a month later, Colin arrived at the city of Vatna.

As the largest city in the underground layer, Vatna City was still as prosperous as ever. Colin walked casually and was not in a hurry to find a hotel. Even if it was late, he believed that no hotel would dare to refuse the accommodation of a first-level wizard.

Colin quickly found the shop he had been to last time. The shop owner didn't recognize Colin anymore. Seeing that it was an official wizard visiting, he received him very carefully. Colin didn't point it out, but just walked around casually and left the shop.

In the past, when Colin didn’t have the financial resources, he never went into larger stores. Not only could he not afford the products, but he was also afraid of attracting the disgust of some big shot. Now that he has been promoted, he is not afraid of being bullied by big stores even if he doesn’t buy anything.

Besides, Colin came to the underground world this time not only to find a few friends, but also to take the opportunity to trade in supplies and replenish his financial situation.

Colin casually walked to a shop that looked quite large, looked at the name of the shop - Malkado Alchemy Shop, and walked in.

"Hello, sir, is there anything you need?" Seeing the wizard Colin enter, the shop owner walked around the shop staff and asked attentively.

“What do you mainly do here?”

"We mainly sell some alchemical products made by masters, and of course there are some other items as well."

"Oh, are there any special alchemical products?"

"Yes, there are vest armor made by Master Malcador, and light cloaks made by Master Svenlin, and some ordinary alchemical gadgets. The key is to see what you need."

"Do you sell alchemy potions here?" Colin had no plans to buy anything for the time being, but instead wanted to sell some items.

"Oh? Are you also an alchemist? Of course we will buy your potions. If you can provide a long-term and stable supply, we can increase the price appropriately."

"Are we doing business here?" Colin asked, looking at the other customers in the store.

"Oh, it was my negligence. Please follow me." As he said that, the shop owner took Colin out of the hall and into a room.

"Sir, please rest assured that no matter what potion you want to sell, I dare not say that the price I offer here is the highest, but it will definitely not be low. Besides, I dare not cheat you of your money."

Colin used his mental power to check the space ring in his hand and got a detailed number in his mind.

"Well, I have 1000 bottles of primary mental power potions, 2000 bottles of primary recovery potions, 2000 bottles of primary strength potions, 600 bottles of intermediate mental power potions, 500 bottles of intermediate recovery potions, 500 bottles of intermediate strength potions, and 210 bottles of advanced mental power potions. Please do the math."

"...Sir, how about this: 5 wizard coins per bottle of primary mental power potion, 4 wizard coins per bottle of primary recovery potion, 5 wizard coins per bottle of primary strength potion, 16 wizard coins per bottle of intermediate mental power potion, 13 wizard coins per bottle of intermediate recovery potion, 14 wizard coins per bottle of intermediate strength potion, 60 wizard coins per bottle of advanced mental power potion, a total of 5 wizard coins. I'll give you 9 wizard coins."

"Well, sure." Colin thought for a moment and came up with the same amount of money.

The shop owner took out 5 wizard coin cards and 9000 wizard coins and gave them to Colin.

"Sir, if you still have potions to sell, you must come to my shop. I can give you a better discount next time." The shop owner said happily. He made some money today. This sir must be a hidden master of potions. He has so many potions, enough for me to sell for half a year.

After Colin got the money, he left the Malcador Alchemy Shop. After leaving the shop, he made a simple estimate and found that he had made a profit of 3 wizard coins.

Hey, this is a really good business, no wonder they say businessmen are the most unscrupulous. I can earn several times more than guarding Willisel. It's a pity that I am really not suitable for this, otherwise I could make several trips back and forth several times a year.

In addition to a large amount of food and some of his own belongings, Colin has emptied three space rings.

After selling the things, it was time to get down to business. The first people Colin contacted were Beta Bloodhoof and Kobe Bloodhoof. Luckily, they were both in their own tribe. After agreeing to come to Colin in a few days, they ended the correspondence.

Well, let’s find a hotel to stay in first. It will take Beta and the others a few days to get here.

There was an inn on the side of the road, and the fee was 50 gold coins a day. Colin, who had just made a fortune, paid a month's room fee directly.

Lying on the bed in the hotel, Colin was not ready to rest yet. He was casually thinking about some difficult problems encountered in the experiment. Before he could figure out anything, he was interrupted by a knock on the door.