Stone Bones p. 84
Stone Dragon
You focus your energy to enhance your defenses, drawing on the power of your weapon's impact with a foe to toughen yourself against a counterattack.
The Stone Dragon tradition teaches its disciples to shrug off attacks through a combination of mental focus, pure tough- ness, and resilience. When you make a successful melee attack, you attune your mind and body to such an incredible extent that only the sharpest weapons can injure you. Lesser armaments cause mere bruises and minor cuts.
When you use this maneuver, you make a single melee attack. If this attack hits, you gain damage reduction 5/adamantine for 1 round.