Once again recorded:

2 wind runes, 3 water runes, 3 fire runes, 2 earth runes.

After two rounds of exchange.

It was one step closer to the requirements for Intermediate Rune Base Upgrade Scroll.

Iron, copper, wood, and stone had already exceeded 200 units.

Each rune required 20 pieces.

The wind runes and fire runes were sufficient. He was only short of 3 earth runes and 4 water runes.

Soul requirement was 30. There were already 50 souls, which was far more than needed.

Gold, silver, and crystal required 20 units. Currently, he was only short of 1 crystal.

'Taking advantage of the lunch break to gather the materials, I'll level up the runic base.'

After Klein finished clearing the materials, he opened the trading market.

First, he settled on the crystals.

After a simple search, he found quite a number of players who were selling them.

1. The trade requirement is 1 meat, or 200 ml of water.

Klein chose to trade with meat.

He gathered the materials.

He was left with 3 earth runes and 4 water runes...

Klein scanned his surroundings.

Most of the runes were only used to exchange for weapons or blueprints. They rarely exchanged for food or water.

There were a few times, but the moment they were put up, they were immediately snatched away by others.

Klein racked his brains for more than ten minutes and only succeeded three times. He exchanged for 1 wind, 1 water, and 1 fire.

When he lost his patience, a runic crossbow and a magic cup were successfully sold!

[System notification: Excellent Magic Cup-1]

[System notification: Transaction completed. Water Rune+2]

[System notification: Perfect Runic Crossbow-1]

[System notification: Transaction completed. Wind Rune+5, Fire Rune+1, Water Rune+1, Earth Rune+1]

The two messages were one after the other.

The runic crossbow and magic cup were purchased by the same person.

The materials for the Intermediate Rune Base Upgrade Scroll were still not gathered.

Two earth runes short!

Klein decided to lower the price of one of the runic crossbows.

From 8 runes to 6 runes.

'Colleagues, continue scrolling through the trading channel.'

Fifteen minutes later.

Klein didn't need to wait for the runic crossbows or magic cups to be sold. Roger and another member of the regional channel returned the runes one after another.

They could have given 2 different runes.

However, Klein emphasized the need for earth runes.

Roger returned 1 earth rune and 1 water rune.

The other person also had 2 earth runes.

Only then was the materials needed for the intermediate level upgrade gathered!

At that moment.

Klein removed the intermediate rune base upgrade scroll and held it tightly.

Once used, the resource consumption would be huge.

'I wonder what will happen after this upgrade?!'

He was more or less looking forward to it and excited.

This wave will consume more than half of my wealth. I hope that the upgrade will bring a pleasant surprise.

"Come, use the scroll!" Klein read.

Another large amount of materials had been deducted.

Klein felt his heart ache.

The scroll in his hand glowed with silver light!

It was similar to the last time.

It turned into a lot of ashes.

The number of ashes increased like a black mass of mosquitoes.

They flew in all directions.

The entire runic base began to tremble slightly.

Wherever the ashes went, the ground, ceiling, and walls were growing larger and taller.

It was a visible change in speed.

Little Fox was slightly calm. She had experienced it the last time.

Little Wind looked around, not knowing what to do.

[System notification: The runic base has been upgraded!]

[System notification: Perfect Runic Base>Rare Runic Base]

The trembling of the runic base gradually lessened.

It regained its stability.

"Is this the upgraded base?"

Klein looked around.

The runic base was completely different from before.

The interior was resplendent, like a hall.

Now, he was upgrading the hall on the second floor of the runic base. Just the size of the hall had doubled.

The entire floor was no longer square. It seemed to have become circular.

Klein came to the back and found another room.

Furthermore, the bedroom was very spacious.

There were glass windows, and the bedroom had more light than before.

Klein went to the stairwell again.

Looking down, it was no longer just the second floor, but a full five floors!

"The area has expanded quite a bit. There are three more floors!"

Klein was surprised and delighted.

He went down to the fourth floor to check.

There were bedrooms, kitchens, and a hall.

The area was larger than the previous floor.

Then, he went down to the third floor.

The layout was slightly different.

The entire hall was like a training ground, with targets, sandbags, and the like.

The floor area continued to increase.

He went down another floor.

The second floor was empty, and the area expanded a little.

Finally, there was the ground floor. The area had increased the most, roughly three times the original size.

All the buildings that had been built before were still there.

The first floor was a little messy, but after the upgrade, it became a little empty!

"Let's take a look outside."

Klein pushed open the large iron door and walked out of the runic base.

Phew!

He flew into the air.

The entire catacomb was large and tall enough.

The upgraded runic base occupied more than half of the catacomb.

The highest point of the base was almost touching the top of the catacomb!

Height...

"Thirty meters!"

"This..."

Klein floated in the air and spoke in surprise.

He asked, "Has the style of an ancient castle transformed into the style of a tall tower?"

The entire runic base's style had changed drastically.

From the outside, one could clearly see that the base was divided into five sections. From the bottom to the top, it was gradually shrinking.

It was like an ancient stone tower!

Many patterns were carved on the walls outside. They were lively and ancient.

The overall color was not monotonous.

The gold was the main color, while the dark was the supplementary.

From afar, it looked majestic and magnificent.

Klein flew around the runic base, and the more he looked, the more satisfied he became.