Stone Plating

That part of your chest has began to quiver from time to time, and you can swear that it moves a bit with each passing week; until recently. Focusing in on the spot, you can feel the tendrils of the wicked power that charges it growing, leeching further into your body. Honing further onto that power, you realize that you can slightly manipulate it, changing it's shape and location. 

• As a reaction, you transform a part of your body into stone, mitigating some of the damage that you would have been dealt. When you activate this ability, gain 3 Stone Plating dice, each one is a d4, until the start of your next turn. When you take damage from an attack, you can roll any number of your Stone Plating dice to reduce the damage from that attack equal to the total number rolled. Regain all Stone Plating dice after a long rest.  
• If an friendly creature is within 5' of you, as a reaction, you can expand 2 Stone Plating dice to either block a d4 of damage, or lower the attack roll by d4. You must choose which option you are enacting before the DM tells you whether or not an attack hits.