Nullifying

This special ability can only be placed on melee weapons. A nullifying weapon suppresses a creature's spell resistance for a short amount of time. Anytime the weapon strikes a creature with spell resistance and the creature takes damage from the weapon, the target's spell resistance is reduced by 1 for 1 minute. On a confirmed critical hit, its spell resistance is instead reduced by an amount equal to the weapon's critical multiplier. Multiple hits from a nullification weapon stack.