From the back of the box:
Restore the planet. Plastics. Poisons. Nuclear waste. Ozone destroying gases. Genetic mutations. There was no end to what man did to make Earth uninhabitable. And now man wants to reclaim it.
Specially trained ecological engineers called Environmental Purifiers (EPs) are being sent to Earth to undo centuries of damage. Is it too late? You're about to find out. Because you are one of our best EPs.
You will enter the Earth's hazardous atmosphere in a plasmic hoversphere. Then begin by destroying radioactive nodes and obelisks. You will build land and fly across oceans. Avoid mutant strains of experimental species like poisonous Viral Trees and deadly Eco-Eggs. Watch out for wandering Necromancers and sweeping air purifiers.
There have been others before you and we may as well tell you the truth: No one has returned alive. But you can do it. Because you have one thing the others did not: A love for the Earth.