The Red Glow
Once a daughter of Karn, a demigod of the earth and stone, she took an aspect of the living fire that flows through the world. But she chose instead to use her nature to burn and destroy and she was cast to the Umbral. Now the Blood of the World is an entity of living magma that perpetually glows with the light of molten rock.
The blood of the world descends within the umbral, taking her seat at the center of a great river of lava. She travels between blackened volcanoes, crawling up through the pools of heat to then walk into the world.
Occasionally the blood of the world spreads out through the world, seeking stone and metal to meltdown and add to itself. Some dwarves revere the blood of the world, especially after they are lost in the deep dark of the vaults. They know that if they should ever stumble upon an uncontrolled seam of her magma it could possibly be their final sight.