Needs review
Source: Rokugan Campaign Setting

Description: Rage flows through your veins; you are ready to make the ultimate sacrifice

Prerequisites: Toughness, The Mountain Does Not Move

Required for: Unyielding Fury

Before making an attack roll, you may voluntarily sacrifice your own hit points to inflict additional damage. For every two hit points you sacrifice you do 1d4 damage to your opponent if you hit. You may not sacrifice more hit points on one attack than your Constitution modifier. Your own hit points are lost whether or not you were successful.