Worse yet, the xenofungus acts as a home to Mind Worms, which randomly boil out of the fungus and attack human settlements by psychically stunning their victims with fear, burrowing inside their brains, and placing their ravenous larvae inside, causing the hapless victims to die a Horrible death, with a capital H. The local "flora", known as Xenofungus, covers much of the surface and prevents settlement or even easy transport where it occurs. The atmosphere is far too light on oxygen and heavy on nitrogen, forcing anybody exiting sealed colonies to wear oxygen masks (with the only saving grace being that at least they don't need pressure suits), and that's the least of their concerns. Upon their arrival, however, everybody finds, to their horror, that Planet is not nearly the safe haven they had hoped for.
In 2060 AD, the Earth was one hell of an awful place to live, torn apart by war and sunken into disgrace by poverty and ecological damage.