Chaos Rage (3.5e Feat)
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Chaos Rage [Anarchic]
The power of chaos increases your rage ability. While raging, your muscles shudder with uncontrolled energy as a spirit of chaos pushes you past your physical nature.
Benefit: Your effective barbarian level increases by +4 for the purposes of your rage ability. This feat can't increase your effective barbarian level beyond your Hit Dice. However, if you can't benefit from the full bonus immediately, but later you gain nonbarbarian Hit Dice, you may apply the rest of the bonus. This does not affect your trap sense, uncanny dodge, or any other barbarian class features. It only increases your effective barbarian level in regards to using your rage ability.