Trains are the fastest way to move something across Equestria, no matter how big. A heavy stone sarcophagus, for instance, one brimming with dark magic. The Royal Guard just launched a raid to retrieve it from the hooves of sinister cultists.

Now, the survivors of that raid are stuffed in a train crossing the wilderness. Just them, the skeleton crew, and the sarcophagus. Guarding it until they can get reinforcements at the next station ought to be easy. After all, there’s nothing else alive for miles. Right?

Wrong. There’s something on board with them. Something after the sarcophagus. Something that doesn’t care what stands in its way.