What lies under the turf deep in the earth of that grassy mound? The PCs would very much like to know...
Inspired some years ago for a Kult/CoC Halloween game
Knowledge is Power. That is, he who makes the knowledge, wields the power.
A fey spirit masks itself as a bee which investigates all who travel within a specific section of the forest. Any the bee finds worthy are allowed to see the hidden opening into the fey kingdom, just off of the trail. Any deemed unworthy see only the bee, buzzing around around them momentarily before moving on.