So I think that the mythology for season 6, or at least some of it, will be centered around the Wild Hunt, which Noshiko mentioned at the beginning of season 5. I’ll just point out a few reason why I think so. These are all from wiki.

This man is riding a horse in the s6 promo and one of the descriptions online about the rider in the wild hunt is

“In Älghult in Småland, it was safest to carry a piece of bread and a piece of steel when going to church and back during Yule. The reason was that if one met the rider with the broad-rimmed hat, one should throw the piece of steel in front of oneself, but if one met his dogs first, one should throw the pieces of bread instead.”

And it’s rumored that Stiles would go missing in some way.

People encountering the Hunt might also be abducted to the underworld or the fairy kingdom.[4] In some instances, it was also believed that people’s spirits could be pulled away during their sleep to join the cavalcade.

In MTV’s hit show Teen Wolf, Jordan Parrish is a Hellhound of the Wild Hunt.

There’s a lot more than this, but those are just some of the one’s that stuck out to me.