章 350: Chapter 348-cornerstone in hand, the Otherworld hunting ground

Tang Zhen played with the three million Yuan Tower Foundation stone for a while before putting it into his storage space. He wasn't in a hurry to build the tower.

He was going to wait for a while more. When the main tower was promoted to Level 4, he would take out this foundation stone and promote it to Level 4 together!

To upgrade from level three to level four, Lou Cheng needed to sacrifice 10000 level four brain pearls, which was equivalent to 10 million level one brain pearls!

To Tang Zhen, this was not a small burden.

Currently, he only had less than ten million brain beads left.

Moreover, in Tang Zhen's plan, he didn't need to upgrade just one tower, but three!

Upgrading the main building and the mother tree, Lou Cheng, required twenty million brain beads. Upgrading Lou Cheng, which had a protective shield, to level four required eleven million brain beads.

In total, there were more than 30 million brain beads!