When Agent Reyes is driving her Dodge Intrepid, and is contemplating about smoking or not, her car dies. You can see clearly that the car's temperature gauge shows that the engine is still cold, although she clearly has been driving for a while. See more
I once had a talk with Mulder about starlight. How it's billions of years old. Stars that are now long dead whose light is still travelling through time. It won't die, that light. Maybe that's the only thing that never does. He said that's where souls reside. I hope he's right.
If you're trying to prepare yourself I want you to stop. Nothing says that we're going to stumble over him in some field. Nothing says he won't be fine.