The Hollow Hart's Threefold Gate

You enter a circular clearing where the trees twist inward like ribs around a sunken stone altar. Green witchlight glows beneath the moss, and the air smells of wet bark, old smoke, and copper. Three sockets interrupt the altar's surface: a root, a crescent, and an eye. Around them, standing stones bear faded cult sigils. Somewhere beneath the earth, something gives a slow, patient knock whenever the wind falls silent.