Iron Blooded - Seven: Brood Mother

In a modern world where cultivators need a place to cultivate or vent their boredom, there are private businesses that set up instance dungeons with the aid of technology and cultivation magic to enable cultivators to train and commoners to experience the life of cultivation. They are called dungeon suppliers.
Xie Jin's one and only dream was to be a dungeon supplier and when his only relative passed away, the relative's inheritance gave him a plot of land and surprisingly, a 'System' Module which the relative had previously used.
With the help of the system, Xie Jin decided to pursue his dream of becoming the number one dungeon supplier.

“I thought I was dead, but when I opened my eyes, I found myself reincarnated in an abandoned RPG game. I intended to gather the heroes I had trained to form a guild once again, but…“I thought I was dead, but when I opened my eyes, I found myself reincarnated in an abandoned RPG game. I intended to gather the heroes I had trained to form a guild once again, but…Hmm… it seems all the heroes have completely lost their minds.”

An unexpected journey took a group of university students into a secret room from which, upon returning, they began to disappear one by one. In order to unravel the mystery, they joined forces, traversing heaven and earth, diving deep into seas, crossing the farthest corners of the world, and even daring to time travel, only to find that behind each puzzle lay yet another.

The empire has turned into the land of the undead due to a spell gone wrong. God summoned heroes from countless worlds to purify the empire and plant new hope. Lee Shin Woo, an ordinary earthling, was also summoned. As an undead, that is.