Find the Weak Spot, Greater (3.5e Feat)
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Greater Find the Weak Spot [General]
You are able to find the weak spot on non-living entity allowing you to critically damage it.
Benefit: May now reduce by 75% the chance of negating a critical hit (treat immunity as 100%). This feat also affect sneak attack and similar abilities.
Normal: You cannot critical hit undead, construct, elemental and others.