At the heart of a natural cave there is a giant geode. It got cracked open at one side and revealed an astonishing view. The Insides are covered in bright, shining crystals of different colours. The local natives who first discovered this place thought it was a piece of the heavens that were brought to earth and prepared a shrine inside the geode. Now they come here regulary to honour the gods and seek guidance.
Little do they know about the intense magical background radiation that will slowly turn all of them into crystals and make them servants to the crystal plane.