Insurgent weapons cache

A group of Stygian Insurgents gather on the deserted outskirts of an imperial colony.  There they equip themselves from the weapons cache that had been secretly deposited there months in advance.  Now well armed they are free to strike suddenly into the colony with far more firepower than the imperials believe possible.  The Alpha Legion and Stygian Empire used these weapon caches to further insurgency across the sector and draw Imperial forces into new battlefronts that quickly became quagmires of insurgency warfare.