Deflection

You wave your hand toward an attacker, briefly placing a magical barrier between you. The damage you take from the triggering attack is reduced by 1d6, as you deflect some of it. If you reduce the damage to 0, you can turn the deflected damage back onto your attacker. Make a melee spell attack against the attacker. On a hit, the attacker takes force damage equal to the amount of damage you deflected. 

The damage you can deflect increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).