When running a Call of Cthulhu game, you have to know what the endgame is for your antagonists. Are they trying to achieve power for power’s sake, or are they trying to set a Great Old One free? Some Great Old Ones can bestow great powers to the humans who are in direct service to them. They gain spells and abilities that are otherworldly. These affected characters could be your game’s BBEG.
Or the wards holding back the Great Old One might be shattered, allowing the god to enter our world. As Keeper you need to know how far you’re willing to go. Unleashing a Great Old One is terrible fun… unless you’re an investigator standing in the Great Old One’s way.
In the Malleus Monstrorum, the encyclopedia of Cthulhu Mythos monsters and deities, it reminds Keepers that investigators to a Great Old One are no more than ants to a human. The human doesn’t bother to know the names of the ants standing on the ground in front of him. They don’t try to communicate what they watched on Netflix last night. How do you explain Netflix to an ant?
In the end, the person might decide not to alter his path and step on the ant.
Such is the fate of an investigator standing in the way of a Great Old One.
Mundane weapons are useless when targeting Great Old Ones. There might be a vulnerability to an element, like fire or water. Otherwise, you need to rely on spells to cause significant damage. Does anyone in the investigating party know any devastating spells yet?
There’s a chart in the Malleus Monstrorum that shows the amount of damage a range of weapons do to the gods. Most of the damage is negligible, unless you manage to immerse a god in a nuclear explosion. That can kill the god. But not kill like we know it. The god’s zapped from this plane of existence back to where they came from and regenerate at whatever rate a god heals from such an encounter. Then, the god can go right back into the thick of things. In the long run, even reducing a god to zero hit points is a fruitless victory. The god will come back and be quite angry.
So, you’ve got your players in a fight against Cthulhu or one of his brethren. What’s the best the investigators can hope for? They can best hope to banish or bind the god back from where it came from.
As pointed out earlier, it might not be necessary to bring out the gods. They can act through their chosen ones on this world. These people are given supernatural abilities and work to accomplish tasks which might make no sense to anyone else.
One cultist might be ordered to sprinkle salt on the Queen of England’s rose garden. It seems like a high-risk low reward task, but to a Great Old One it might break a ward that is preventing the god from manifesting anywhere but in its celestial prison. Maybe the cultist thought he was supposed to salt the Queen’s rose garden, but how can he be sure that’s what the god wanted? He’s interpreting maddening visions imparted on him by a completely alien being. He may have misunderstood the mission completely and is now on the loose creating a high level of mayhem.
In other words, even if the cultist is successful in performing the god’s task, there might not be any cosmic consequences. Things were misinterpreted. However, if the cultist is caught, the investigators now are in possession of a conduit to an elder god, which can be the seed for many future adventures in the campaign.
