Global Collapse: Infinite Upgrade Shelters

Story of: Global Collapse: Infinite Upgrade Shelters

Global collapse.

All human beings will face survival challenges.

Super radiation, high temperature heat waves, extreme cold ice and snow, terrifying beast tides, alien aliens...

Build a shelter to start unlimited upgrades.

Iron door - Steel door - Alloy door - Titanium alloy door -

Wooden wall—Iron wall—Steel wall—Alloy wall—

Generator - Bio-generator - Bio-energy storage device - Bio-energy nucleus -

Robot—AI robot—intelligent AI robot—super-intelligent AI robot—