When you imbue your weapon with arcane energy, you can expend transmutation power to enhance one of your ability scores.
Benefit: When you activate your Arcane Strike feat, you can expend an unused transmutation spell that you have prepared or a spell slot of a level in which you know at least one transmutation spell (for spontaneous casters). If you do, each time you strike and deal damage to an opponent before your arcane strike ability ends on your next turn, you may choose to temporarily increase one of your physical ability scores by 1 until the ability ends, to a maximum of 1 increase per level of the spell expended. You may choose to increase a different ability score with each successful attack, and you may choose to increase the same score more than once.
Undefeatable: The Collected Feats Sourcebook, Copyright 2009 – 2010, Louis Porter Jr. Design, Inc. Undefeated, Copyright 2011, Louis Porter Jr. Design, Inc.