Versatile Weapon

Transmutation
Level: Artificer * 3, Bard * 2, Bloodrager * 3, Hunter * 2, Magus * 3, Ranger * 2, Sorcerer */Wizard * 3
Components: V, S, M (iron filings)
Casting Time: 1 Standard Action
Range: close (25 ft. + 5 ft./2 levels)
Target: one weapon or 50 projectiles, all of which must be together at the time of casting
Duration: 1 minute/level
Saving Throw: Will negates (harmless, object)
Spell Resistance: yes (harmless, object)
  You transform the physical makeup of a weapon as you desire.
  This spell functions like greater magic weapon, except that it subtly alters the physical properties of a weapon, enabling it to bypass Damage Reduction of one the following types: bludgeoning, Cold Iron, piercing, silver, or slashing. The affected weapon still inflicts damage of its normal type and its Hardness and hit points are unchanged. This spell can be cast on a Natural Weapon or unarmed strike.