Enervation

In an oxygen-deprived world felled to its knees from overpollution, humanity stands on a bare thread of existence, with the majority of Earth's land flooded from global warming, with entire civilization destroyed - sunk beneath the waves. Humanity is forced to carry around their own oxygen sources - rare, lab created plants converting the carbon dioxide in Earth's air into breathable oxygen. They are the only plants alive now.

Ilina Council has lived her entire life in Gaia, one of the last human settlements in the world today. At her graduation ceremony at age 16, when people are given their job assignments for life, Ilina is chosen to be integrated into the Institute, where a chosen number of youths are selected each year to research better ways for human life and future survival.

In the ruined, fields of rubble and broken down buildings, Ilina makes a shocking discovery - a small plant surviving in the rocky outcrop despite the odds. Secretly studying this shocking new find, Ilina finds that there is a whole other civilization below their feet, where people have been living and have evolved over the course of thousands of years. They've evolved differently, suited to underground life, and Ilina finds a long lost person there that she thought to be dead. And there's something else down there too, something that the Gaian government would kill to get.

Air.