Magnetic Pinions

Small pieces of metal fly from you, propelled with magnetism at great velocity. Make ranged impulse attack rolls against up to three creatures within 60 feet of you; you gain a +1 circumstance bonus to your attack roll against any target wearing metal armor or made of metal. All three attacks count toward your multiple attack penalty, but it doesn't increase until after all the attacks. The metal pieces deal (((your level − 1) ÷ 2, rounded down) + 1)d4 bludgeoning plus (((your level − 1) ÷ 2, rounded down) + 1)d4 piercing damage on a hit (or double damage on a critical hit).

Level (+2) Each type of damage increases by 1d4.