Shamanic trance is just a more primal method of the “scientific” method.
Shall we discuss specific species of dark fey? It will help if you identify a dark place for me. They are otherwise too numerous for me to make an exhaustive catalogue.
My laundry room. Ok, that works. Brownie. Also known as Kilmouli. They were not originally dark. They were called Brownie only because of what they looked like. They typically appeared to have fur or thick hair, or be dressed in fur.
Bedroom closet. Oh, same for that as well.
What made them go dark? What made the Brownies go dark is the change in human attitudes toward domestic animals. Humanity used to treasure its horses and dogs and cats as Brownies bonded with these creatures.
Factory farming? Yes. Brownies see factory farms as evidence of human evil, almost unforgivable. Brownies are fey farmers.
My laundry troubles will clear up if I get a cat? Not likely. You actually would have to recognize your Brownies presence, now. In the past, this was not necessary.
You have to talk to him? Yes, and then perhaps if you showed empathy toward animals around the entity, it would decide to make peace with you.
What can I do to appease him/her? Creating in miniature the circumstances they originally bonded with. They like house plants.
My plants are dying too. Neglecting the plants will anger Brownies.
Plants like music. Play them some uplifting songs? Brownies like music also.
How about a room that is always cold no matter how much you try and heat it? As for strange cold basements, do you hear weird pings in the plumbing? Do you hear weird knocks there? The house is shifting a lot. You might be living with a Knocker.
You find stuff getting buried a lot? Find anything of precious metal goes missing? Knockers consider precious metal to be theirs.
Your thoughts are welcome. Be well friends.