Stunning Fist (3.5e Feat)
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 Stunning Fist [Ki Manipulation]
By channeling Ki Energy your unarmed strikes have the ability to stun your foes.
Benefit: You must declare that you are using this feat before you make your attack roll (thus, a failed attack roll ruins the attempt). Stunning Fist forces a foe damaged by your unarmed attack to make a Fortitude saving throw (DC 10 + 1/2 your character level + your Wis modifier), in addition to dealing damage normally. A defender who fails this saving throw is stunned for 1 round (until just before your next action). A stunned character can’t act, loses any Dexterity bonus to AC, and takes a –2 penalty to AC. You may attempt a Stunning Fist once a round at cost of 2 Ki Points. Constructs, oozes, plants, undead, incorporeal creatures, and creatures immune to critical hits cannot be stunned.