Serial Peacemaker is a masterwork bastard sword.  It counts as magic for the purpose of overcoming damage reduction. 

Protect the Innocent: As a swift action, you may designate any non-evil individual within 100ft to gain Serial Peacemaker's protection.  All hit point damage dealt to the individual is reduced by half (rounded down); the remaining damage is transferred to you.

Swift Response: Serial Peacemaker can be drawn as a free action.

Resounding Retaliation: If you have fewer than half your normal hit points, Serial Peacemaker deals an extra 1d8 points of sonic damage on a critical hit.  If you have fewer than one quarter of your normal hit points, Serial Peacemaker's critical strike range increases to 17-20.