You can charm people into lowering their defenses, allowing you to ambush them more effectively.
When you succeed at a Diplomacy check to change a creature’s attitude, you can draw a weapon and make a single melee attack against that creature as an immediate action. If you changed your target’s attitude to friendly or better, your target is considered flat-footed against this attack. If the target survives, it takes a –2 penalty on its initiative check for this combat.
Once you attack a creature, its attitude becomes hostile.
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SECTION 15