Once per day as an immediate action, you can call upon the forces of destruction to weaken your opponents' defenses. If you deal damage with a melee attack (but not a melee touch attack) while this ability is active, you temporarily reduce the struck opponent's armor bonus or natural armor bonus by 1. Reductions from multiple hits stack, to a minimum bonus of+0. If the opponent has both armor and natural armor bonuses, it chooses which one to reduce. Once one bonus reaches +0, the other bonus automatically gets reduced until it too reaches +0 or the effect ends. This effect lasts for 1 minute, after which all armor and natural armor bonuses reduced in this way return to normal. Upon reaching 10th level, you reduce your opponent's armor or natural armor bonus by 2 per successful hit.