Main 3.5e FAQ
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Does a dragon with Power Attack add twice the number
subtracted from attack rolls to damage rolls when making a
tail slap?
No. While it shares some mathematical similarity to a twohanded
weapon, the tail slap (or any other natural weapon that
adds 1-1/2 the creature's Strength bonus on damage rolls)
doesn't gain any other benefits applied to the use of a twohanded
weapon.
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