People talk about the Zone as a place where time does not pass, but that isn't what makes it terrible. It's the creatures that give it its name. They feed on your fear by making you live it. They're like shadow spores that creep inside you and infect everything good and right. And then turn it against the host. Eventually, you forget that the phantoms are doing it to you at all. Your nightmare becomes your reality. That's when you go insane.