Abyssmarine

Abyssmarine is a dark stone which lines the walls of the Abyssal Chasm. Multiple Deep One Structures are made of this substance, as well as the Deep Altar. It has strange, otherworldly properties as when a Deep one interacts with a Deep altar touching any chiseled Abyssmarine, it lights up with white lines along the entire structure. Like all stone blocks, it has slabs, pillars, bricks, and a chiseled variant.