Global Catastrophe: It Starts with Upgrading a Shelter

The apocalypse breaks out, and disaster descends.

An intercontinental missile cuts across the sky and slams into a colossal meteorite nine thousand meters above the ground!

Earthquakes, tsunamis, surging radiation, an ice age!

Countless extraterrestrial creatures arrive on Earth among the meteorite fragments, turning the world into a living hell!

[Hello, Host. You have returned to fifteen days before the calamity. The God-Tier Shelter System has been activated.]

[To protect your safety, please complete the shelter upgrade missions as soon as possible!]

That day, Zhang Xiaofan opened his eyes, immediately pulled up the God-Tier Shelter upgrade menu, and muttered to himself.

"The exoskeleton combat soldier program has been launched. The orbital paratrooper technology should be finished by tomorrow, too."

"Oh, right, the defensive installations. A photon laser cannon is an absolute must, and I should probably build a few hundred more mechanical guards..."