Catty Catty Catty

As disaster was about to strike, a group of survivors transmigrated into a desolated world and were challenged to a game of survival. From terrifying acid rains, to endless natural disasters, the heavens burn while the earth scorches, radiation is rampant, and nobody is spared from the dangers of this hellscape. The only way one survives is by building a shelter and slowly upgrading it in hopes of surviving another day. 
Luckily, Su Mo awoke a Doomsday Survival System that allowed him to infinitely level up and upgrade his shelter! The main shelter wooden door can be upgraded into a metal door, which in turn upgrades into a composite gate; the wooden spears can be upgraded into bronze spears, which eventually upgrade all the way into electromagnetic spears... While everyone struggled to survive, Su Mo was fully loaded, and well equipped to dominate the post-apocalyptic world. 
"While some of us are lighting oil lamps, he's been using refrigerators!" 
"The walls in his shelter alone are tens of meters thick, it's the safest place on this planet."
"Before I die, I wish to spend one day in his shelter..."

EndlessFantasy Translation 

My Post-Apocalyptic Shelter Levels Up Infinitely!

LambSheepMutton

After the six-hour trading period, it was three o'clock in the afternoon when Su Mo stepped out of the door of light. The golden light behind him shattered twenty or thirty seconds later.

The light gradually turned into a spot of light, fell to the ground, and melted into the drifting snow.

Except for the shelter and the mountain of materials piled up at this time, the peaceful scene in the basin had once again been restored.

3200 units of iron were divided into two layers and densely covered the surroundings of the Underground Shelter, covering an area that spanned three or four acres.

It was the same for the blocks of copper, which lay neatly on the ground on the left side of the Underground Shelter.

Given the current space within ​​the Underground Shelter, these materials could not be stored even if the shelter doubled in size several times. They could only be temporarily piled outside.

Build A Gun, Establish The Firearm Technology Tree!