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

Li Hu carefully inspected the door for a while but could not help cursing out after realizing there was nowhere for them to start.

The black iron door was 2.7 meters high and 2.4 meters wide. After examining it, he found neither buttons nor a traditional keyhole that could be used to open the door.

It was like a gigantic wall with no possible way to break through it.

Before seeing it himself, Li Hu would have never believed that some maniac built a door like this.

'What kind of idiot would design a building with no entrance or exit and not even a place to insert a key?

'Is it possible that the door functions on a mechanical structure supplied by power?

'What happens if there's a power outage?

'Or what if the mechanical structure gets damaged?

'Any minor accident would make the door completely unfunctional, and there would be no other way to open it except to destroy it.

First Time Opening the Door, the Seven Alphabets! Part 1