Plan A

Plan A: "Defile their holy places."

Plan A was first successfully implemented in Legendary when the PCs found themselves being pursued by an army too powerful for them to defeat alone. Realizing they were close to the territory of another antagonist faction made up of religious fanatics, the PCs allowed the the army to pursue them into the fanatics' territory. The PCs then immediately got out of their airship, invaded the fanatics' most important temple, and started demolishing all of the holy items inside in a hit-and-run. When the enraged fanatics left the temple to give chase, they came across the other army on their doorstep, who fought them while the PCs slipped away.

For being such a weirdly specific strategy, Plan A has had surprisingly broad utility across multiple campaigns. For instance, in Project MONUMENT, the hunter PCs purchased a Tactic that allowed them to interfere with the vibe of places that produced mystical energy and make it so they couldn't produce that energy temporarily (I think this Tactic was even called Defile).