The Ancient Magus' Bride: The Boy from the West and the Knight of the Blue Storm S01 E01 Don't be caught by the hunting party.

During a heavy storm, lightning strikes an ancient stone, chipping two pieces off of it. In response, the Wild Hunt appears, but with their leader missing, they begin roaming the forest randomly, much to Spriggan's concern. Meanwhile, Chise prepares to attend the College, but suddenly begins to feel ill. Elsewhere, a young boy named Gabriel has recently moved into the countryside with his parents due to his illness. That night, the Wild Hunt still roams the forest, their deadly aura killing every living being they come across.