The Traveler's Guide to Aellorah
The Stonefolk appeared ages after the Eldenfolk, and are more connected with the natural world, being highly proficient in professions such as mining, smithing, and stone carving. They have a natural ability to become one with stone and pass through it as if it were air. Their skin is much more tough than the other Dwarves, and they prefer to dwell in structures built into mountains rather than the above-ground dwellings favored by the Eldenfolk.
You have a connection to minerals, stone, and dirt that allows you to pass through them like water. Once per day, you can pass through solid stone, dirt, or other natural materials besides metal. While inside these materials, you can move at a speed of 20 ft. in any direction. You can remain inside this type of material for up to 10 minutes, or until you exit the material. While inside, you can sense passages where the material ends, but cannot see, functioning like Blindsight. Maintaining this ability requires concentration, and you cannot cast spells while within the material.
If you are inside the material when the effect ends, you are immediately ejected to the closest unoccupied space, taking 5 (1d10) force damage for each 5 ft. you were moved to arrive there. Any damage to the material you are within while using this ability does not effect you, but can potentially eject you from the material, ending the effect.