Tectonic Arcanist

Your innate magic comes from the power of elemental earth.  You may have been born in a subterranean complex of some sort, or in a natural cavern or cave; Your family could have called a large desert home for centuries, and the frequent sandstorms and gritty lifestyle has finally manifested in you; Perhaps you chose “boulder” during “boulder, parchment, sheers” one too many times.  Whatever the case may be, the foundation of your arcane abilities was forged from the steadfast powers of the Elemental Plane of Earth.

Gravel Speaker

The arcane magic you command is infused with elemental earth.  You can speak, read, and write Primordial.  Knowing this language allows you to understand and be understood by those who speak its dialects: Aquan, Auran, Ignan, and Terran.

Stone's Stability

Starting at 1st level, your connection to the Elemental Plane of Earth has increased the durability of your skin.  When you aren’t wearing armor, your AC equals 13 + your Dexterity modifier.

In addition, when you take piercing damage, you can spend 1 sorcery point as a reaction to make a Constitution saving throw of 10 or half the damage you take, whichever number is higher.  On a success, the damage is halved. This feature can only be used once per round.

Seismic Panoply

Starting at 6th level, you can spend 5 sorcery points and 1 hour to craft a melee weapon from rocks or stone around you: 

• There must be at least 5 cubic feet of material to create your weapon. The source material is reduced to the size and weight of the weapon you craft, but is still made of stone. 
• It is a +1 weapon and is considered magic in determining resistances.
• You are considered proficient with the weapon you craft.
• It takes on the damage dice and type of the weapon you choose.
• As an action, you can spend 2 sorcery points to morph your weapon into another melee weapon.
• This weapon can act as your spellcasting focus.

You can only have one of these weapons at a time, until you reach 14 level, at which point you can craft up to two.  Each of the two weapons can be a +1, or one weapon can be a +2.

Cobbled Heart

Also at 6th level, you are immune to being petrified.  In addition to this, you can spend 3 sorcery points to remove the petrified condition from a creature you touch.

Protective Crust

At 14th level, you can use an action and spend 5 sorcery points to grant you or any creature you can see resistance to bludgeoning, piercing, and slashing damage.  This includes both normal and magical damage.

In addition, critical hits on the affected creature are negated and they cannot be knocked prone. 

This feature lasts for one minute.  It ends early if you fall unconscious.

Terra Form

Beginning at 18th level, you have the ability to call upon the power of a great zaratan.  As an action, you can spend 6 sorcery points to gain the following features:

• Add your Charisma modifier to your AC.
• You gain resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks.
• You gain a vulnerability to thunder damage.
• You can spend an action to send a shockwave through the ground in a 60-foot-radius circle centered on yourself. Those in this area must make a Dexterity saving throw or be knocked prone.  This area is now considered difficult terrain to all except you.
• You can use any spell slot above 3 level to send rocks flying at enemies in a 20-foot-radius up to 60 feet away. They must make a Dexterity saving throw.  A creature takes 10d6 bludgeoning damage on a failed save, or half as much on a successful one.  If the creature fails the save by 5 or more, it is knocked prone.
• You gain the Siege Monster feature, deal double damage to objects and structures, as long as the damage type is bludgeoning, force, piercing, slashing, or thunder.

You stay in this form 2 rounds for every additional sorcery point you spend when you take on the form.

While in this form, you do not have access to the remainder of your sorcery points, so you cannot prolong the feature once you have activated it.