So... my name is Ciaphas Cain, and I am—or, at least, I was—a newly-minted Commissar fresh out of the Schola Progenium. By some horrid twist of fate, I got assigned to the Valhallan 18th and its infamous Commander, which has just been sent to a newly discovered backwater garden world to dispose of its oddly horse-like xeno population.

The next thing I know, I'm stranded on the planet in an alien body, the Xenos’ leader is in a coma for the foreseeable future, and her subjects—despite knowing full well that I was once a member of the same group of Imperials who’d struck her down—have shoved me onto her now-vacant throne for reasons having to do with the fact that my new body has wings and a horn. And I'm apparently a psyker now thanks to that horn, and a stupidly powerful one at that. Oh, and have I mentioned that these xenos expect me to somehow lead them to victory against the trigger-happy Inquisitor that seeks to wipe them off the face of the galaxy with nothing but my savviness, a cunning mind, a silver tongue, the resources of a race completely oblivious to the grim darkness of the far future, and the magical power of peace, joy, rainbows, and orbital friendship lasers? I don't think I had.

Brace yourselves; things somehow manage to get even wackier from there.

This is heavily inspired by Ciaphas Cain: Warmaster of Chaos, and as a result it does not take itself too seriously. If you want a grimdark brutalization fic in which the ponies get slammed with the horror of war, prepare to be disappointed.