Post-apocalyptic survival is an enduring theme in city building games. In Oxygen Earth has, once again, experienced an environmental disaster with the help of human beings. The Earth's crust has cracked, releasing toxic gas that has spread globally with the wind, and only a little oxygen is left. Unfortunately it's also me who, once again, decided to take on the responsibility of leading the survivors, to guide them to build a city in this dire situation. This is the destiny of a city builder lover.