But a Scratch (Combat)Source Ultimate Intrigue pg. 79
Your bravado convinces your enemies that their deadliest attacks are mere trifles, making you seem nigh invulnerable.
Prerequisites: Cha 13, Bluff 4 ranks.
Benefit: When an opponent confirms a critical hit against you with a melee weapon, you can attempt a special Bluff check against that opponent as an immediate action. The DC of this check is the same as the DC to demoralize the opponent with the Intimidate skill. If you are successful, the attacking opponent is shaken for 1 round as if you had successfully demoralized it with Intimidate. Exceeding the DC by 5 or more does not add to the shaken condition’s duration. If you fail the special Bluff check granted by this feat, you can attempt it against opponents who saw you attempt the earlier check and fail, but you take a –2 cumulative penalty on that Bluff check and any subsequent Bluff checks attempted in conjunction with this feat against those opponents for 24 hours.