Survive in the Wasteland, My Shelter Can Be Infinitely Upgraded

When a natural disaster strikes, everyone travels across the wasteland world and faces the challenge of death and survival! Horrible acid rain, monstrous floods, burning cities, global glaciers, super radiation... No one can be spared! If humans want to survive, they can only build shelters and accept the baptism of natural disasters one after another. Fortunately, Sumo awakened the doomsday survival system! His shelter can be infinitely upgraded! Wooden door → Iron door → Alloy door → ..... Wooden spear → Oak wood spear → Electromagnetic spear → .... Diesel generator → Biogenerator → Thermoelectric generator → .... While everyone was rushing to prepare for the next disaster, Somo was already fully equipped and roaming the wasteland world. "We are still lighting oil lamps, and other people's refrigerators are in use!" "I heard that the walls of his shelter are dozens of meters thick, making it the safest place in the world." "I want to live in Sushen Shelter for one day in my lifetime." This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.