Traveling by Mercer Station, a random encounter occurred that involved a woman and her stolen wagon. Since I could see the guy just up ahead, I galloped forward. Having gotten pretty good at shooting other players, this NPC stood no chance and I did an instant head shot on him. I climbed into the cart and spun it around, gently cracking the reigns to coast the short distance back to the woman.
The instant the cart crossed the railroad tracks, it completely upended and sent me flying (naturally, I failed the side quest, too, for wrecking the cart):
But that wasn't the weird part.
Try as I might, I could not get Jack to move from this position. He was not dead, since the game would've displayed the "DEAD" title card and re-loaded the game, but no matter what combination of buttons I pressed, Jack was unresponsive. Apparently he'd whacked his head hard enough to fuse it to the ground, but not enough that it didn't kill him.
Since he was in the road, I waited to see if something would happen, but all that happened was some guy fell off his horse when he hit the cart wreckage.
So, there he lay stuck in his mock crucifixion: