Improved Anima Toughness (3.5e Feat)
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Improved Anima Toughness [Epic, Monstrous]
Beings without metabolism are raised or constructed with animating force. This force now can be used to toughen them beyond the durability of their basic undead or construct frames, increasing their hit points.
Benefit: You gain your full charisma modifier as a bonus to your hit points, as if it were your constitution modifier. You also no longer are destroyed at 0 hp, but have a range of up to -10 hp before dying as if you were a living being.
Special: This feat does not stack with the ability Unholy Toughness.