Improved Razor Bite (3.5e Feat)
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 Improved Razor Bite [Racial]
Your bite becomes stronger, and your teeth are much sharper.
Benefit: When you confirm a critical hit with your bite attack, you deal an additional 1d4 points of Constitution damage to that enemy. Creatures immune to critical hits do not receive the extra Constitution damage.
Special: Your bite attack damage increases to 1d8.