Briar Body

Razor sharp thorns erupt from your skin, dealing 1d4 damage to you for each body part you activate this spell on. The user may be specific in the area the thorns erupt from. If the user has more than standard appendages or body parts, those will roll as 1d6. 

If the player has any toxins, blood-borne diseases, or poisons in their blood, the thorns will be covered in said blight. Grant 1/40 chance to purge said blight on spell use.

When an enemy attacks you, they must roll a DEX save of 3 per each part of the spell user's body that has thorns. Therefore, if all standard body parts have thorns, the Dex save must be 21 or higher. If the attacker fails, they may choose to take a CON save, however, if they fail, they take double the normal 1d8 damage per contact point.

(Standard appendages are: head, torso, back, right arm , left arm, right leg, left leg.)

If an enemy is in front of the player, any thorns on the back will not be used in the calculations. If they are on the side, both the back and torso will be used, but not the opposite side's arm/leg. Thus, no attack may use all thorn areas in calculations.

EG Scenario: Player casts Briar Body on both arms and back. roll (3)d4 then takes damage from roll. Enemy attacks player from the front and rolls DEX save of 6 (3 per arm, disregarding back due to attack placement) enemy fails roll. Enemy chooses to take CON save, fails, takes 2d8 x2.