Terran Soul

Your innate magic comes from the depths of earth itself. You can feel power flowing up into you from the ground as you walk. Sorcerers with this origin can usually trace their magic to the location of their birth. Certain reclusive cults believe that the deeper in the earth a creature is born, the stronger their Terran soul will be. However, being born underground does not guarantee that one will develop these powers - in fact, Terran soul sorcerers are among the rarest. 

Underground Survival

Starting at 1st level, you can speak, read, and write Primordial (Terran). Additionally, you have double proficiency on all Investigation, Perception, Nature, and Survival checks specifically relating to caverns, mineral deposits, or other rock formations.

You have darkvision with a range of 120 feet.

When you reach 3rd level in this class, you learn the darkness spell, which doesn’t count against your number of sorcerer spells known. In addition, you can cast it by spending 2 sorcery points or by expending a spell slot. If you cast it with sorcery points, you can see through the darkness created by the spell.

Stony Resilience

As magic flows through your body, it causes physical traits of your ties to the earth to emerge. At 1st level, you get a +1 bonus to your Constitution.

Additionally, parts of your skin are covered in sparkling crystal clusters. When you aren’t wearing armor, your AC equals 13 + your Dexterity modifier.

Earthen Affinity

Starting at 6th level, when you cast a spell that uses earth or stone to deal damage, you can add half your sorcerer level to one damage roll of that spell. Additionally, you gain resistance against bludgeoning, slashing, and piercing damage.

Rubbleborn

Beginning at 14th level, you can control stone at will. You can expend 4 sorcery points to choose one of the effects listed below. All damage caused by this feature counts as magical for the purpose of overcoming resistances.

Stone Projectile

You summon three small stones of your choice. You can magically shoot this stone at any enemy you can see within 120 feet. You are proficient in attacks at this range while using this feature. You must roll to hit for each stone. The target takes 1d10 piercing damage + your Dexterity modifier for every stone that hits. If your target drops to zero HP before all of your stones hit, you can redirect the rest of the stones towards other enemies within range.

Stonestorm

You summon a magical storm of stones. You can choose to center this storm on yourself or any other point you can see within a 60 foot range. A 20 foot square storm of deadly whirling stones appears centered on the point you chose. You are immune to damage from this storm, as the stones magically avoid hitting you. All other creatures in the storm's range must make a Dexterity saving throw. On a failed save, they take 5d10 damage. On a successful save, they take half that. You can choose whether these stones are sharp (to deal slashing damage) or smooth (to deal bludgeoning damage). 

This storm also picks up enough dirt and debris to lower visibility. All attack rolls and checks relying on sight through the storm are made at disadvantage, unless you are the one making them.

Rocky Terrain

You alter the terrain around you. Choose a 30 foot square area anywhere within 120 feet of you. Sharp rocks jut up from the ground in that area, turning it into magical difficult terrain for everyone except you. In addition, if an enemy is knocked prone in this area, they suffer 3d6 slashing damage. This damage increases by 1d6 at 17th level (4d6) and again at 20th level (5d6).

Cave-In

Starting at 18th level, you master your control over stone. As an action, you can cause large boulders to fall in up to a 20 foot square of your choice, anywhere within 60 feet of you. All creatures in the affected area are knocked prone and suffer 10d10 magical bludgeoning damage. Affected creatures must also attempt a Constitution saving throw. On a failed save, they are knocked unconscious for 1 minute or until someone uses an action to wake them up.

You can only use this ability once per long rest.