I messed with the persistent.sfs and everybody on Kerbin died. Except three clones, which were also the product of me horsing around in the source code. I still don't know what happened, or why those three survived. Jeb, Bill, and Bob were not on Kerbin at the time. They were in Prometheus Station orbiting it, and survived the... whatever that was. A 12-kerbal base on Dres turned into a single, unmanned hitchhiker module. A nearby ascent vehicle survived intact, without anybody in it. The transfer vehicle orbiting Dres had its engines, docking ports, and main fuel tank disappear, and its crew is gone as well. Also, Minmus disappeared. I had a base there. Then I had some debris, a rover, an OAV, and a levitating hitchhiker module. Then I had a levitating everything because Minmus isn't being rendered but its collision box is. KSP crashed while I wrote the previous sentence. All of this started when I went into the persistent.sfs and changed an asteroid's class from 0 to 30, and its mass from 150 to 2000000000.