Lost Mine of Phandelver
Ogrémoch, known as the Prince of Evil Earth, is described as a ten-foot-tall (3 meters) humanoid made of rock and crystal. His eyes resembled chipped obsidian and his body sparkled with mica. This was by no means an accurate description however, as few could claim to have ever seen him.
Within the Plane of Earth, in a fortress known as Stonemire, on a plateau near the border with the Plane of Magma, Ogrémoch makes his lair. The heat is unbearable and fountains of molten stone, smoke and steam were used as decoration. Tales are told of the foundations of the fortress being the entombed bodies of Ogrémoch’s still-living enemies.