Shadows of Vespera
Ancient Kuldu Kraik, the broken dragon, crone wyrm of the high mountains, is a legendary beast that demands blood and sacrifices under a Waxing moon for dark rites, and a waning moon for blessed rites.
Nature deity. Sacrifices, druids, gives birth to mosntrosities and wonders. Womb of the dark earth, sower of blood. Monster deity. Shub Niggurath?
Bad good in some cults, good god to witches and the like. Warlocks make pacts with Kuldu Kraik. Druids draw power from dark and light wells, ley lines that represent the spread of the broken wyrms wings.