Subtle (3.5e Equipment)
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Any weapon with the subtle enhancement has a doubled critical multiplier, not range. For example, a +1 subtle dagger goes from a critical of of 19-20/x2 to 19-20/x4. Ranged weapons bestow this power on their ammo.
Moderate evocation; CL 15th; Craft Magic Arms and Armor, keen edge; Price +2 bonus