Code: Scale does not function for a threat this great.
In the event of a supernatural disaster, the first thing to do is panic. Other threats can be fought with blood, steel, and various scientific techniques of varying ethical standards. With supernatural threats, everything is off the table.
Detecting the threat:
Ghosts suddenly appear as a part of everyday life.
A large beast heralded by four horsemen takes dominion over the world.
Everyone on the planet dies and winds up in a shadowy realm.
Strange markings appear on select individuals, signifying their imminent death or blessing.
Massive monsters rise from the depths of the ocean, emerge from the cosmos, or climb out from under your sink in order to devour the world.
Literally anything else that can’t be explained by science (or even scientifically verifiable supernatural events).
Analyze the threat:
Talk to a priest. Talk to a second priest. Phone the Pope (his number is in the company directory).
Try to figure out if any archaeologists have been exploring dark and potentially haunted tombs.
Consult with museums and private collectors around the world to determine if any ancient tablets containing powerful rituals were stolen (or simply read. Don’t read those things).
Call the Pope again. This time, ensure that you have a Latin translator on hand.
Combat the threat:
You’re pretty much on your own for this one. Do something, because that’s what you’re being paid to do, and if the Earth gets eaten by a giant monster, you’re not getting a paycheck.