You become one with the void itself, you gain the ability to convert your matter into nothingness at will. As a reaction when struck by a weapon attack you can roll a DC14 wisdom saving throw, if it succeeds roll 3d6 and subtract damage from the weapon attack equal to the result of those d6, if it fails then increase the damage you take from the attack by 1d6 psychic damage due to your mind being consumed by the void instead of your body.