Defenders of the Quiet Sky

From publisher blurb:

5th Edition Mini-Dungeon for four characters of level 4

Quiet Sky Hermitage has ever been a place of peaceful contemplation.

Generations of druids have relied upon the solitude and isolation of the hermitage to complete their studies, letting the subtle voice of land and sky inspire their works. But now there is another voice whispering within the forest. It arrived along with a meteor storm late in the season, and it has infected the mind of one overeager acolyte.

If the heroes cannot uncover this creature and counter its baleful influence, all the world may be covered in the spores of a very invasive species.