MLP/Warhammer 30K crossover, Book #1 of an alternate Horus-Heresy path.
For 200 years the Great Crusade has sought to reunify the scattered fragments of humanity's once great confederation, and mankind once again approaches a crossroads. An unlikely soul is thrust into the maelstrom that will tilt the balance of power, for the axis upon which the future pivots is a single human soul: Horus Lupercal.
Now, the dice are rolled on a daring gambit which could alter the course of history. The machinations of ruin and disorder are on the march, knowing that their plans may be forever spoiled. Ideals will arise and loyalties will be tested, for it is the dawn of the 31st millennium, and the galaxy is on the brink of war.