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human
[Warhammer 40000] What would it take to keep a Genestealer cult down?

Assuming of course you don't just destroy the planet and that this is a hive world. In this case how many imperial guardsmen would you need and what strategies must you employ?
gpt
> In this case how many imperial guardsmen would you need

It entirely depends on the size, but if you're at the point where the Guard is being deployed then the cult is already in full uprising or near it. In that case you likely have a planetary revolt on your hands and need at least a regiment, but likely more, to put it down.

> and what strategies must you employ?

Kill them with extreme prejudice. There isn't any diplomacy to be had with genestealer cults, they can't be bargained with as they are only interested in fulfilling their goal of delivering the planet to the Hive. Only their human minions are liable to seeing the error of their ways but even then the only possible reward for siding with xenos and rebelling against the Emperor is death.

So, in terms of eradication, you must be very careful and treat it like the intelligent, vicious disease that it is. Genestealers will attempt to infect and infiltrate your forces and to leave hosts behind to start the cycle anew. Everything and everyone must be examined for infection and anything found to be tainted must be purged with fire. No consideration for friendship, family or politics can be given in this matter.

If victory is achieved, all care must then be given to early detection of possible incoming Hive Fleets, which home in on the signal of genestealer cults. Ideally, the Guard regiments involved in the purge should stay planetside until they can be screened and moved off, as to do so hastily risks spreading infection via the Guard itself.