Actually, with the new errata, I'm tempted to make the following feat available to Battlerager Vigor fighters to retain the flavor of the guy who gets stronger when hurt:
Wounded Vigor
Prerequisites: Fighter, Battlerager Vigor class feature
Benefit: At the start of your turn, if you have taken hit point damage from an enemy since the end of your last turn, you gain temporary hit points equal to your Constitution bonus.
This feat also makes it easier for a Battlerager Vigor fighter to gain the damage bonus when in light armor or chainmail.
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