The productions and dwellings of humans often also have spirits associated with them. Unfortunately, it is really impossible to deal with these creatures. Their activity is unpredictable in scope and frequency and may occur in a particular region or a random scattering. Just hope they decide to show up in a competitor's laboratory. Talking to a god is one of the few occasions when it doesn't pay off to be cocky.
Verification is key.
Before you slaughter your neighbor at the behest of an ancient god, make sure that ancient god isn't just some joker wearing a latex mask.