Chaos Blade (3.5e Equipment)
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Once per day, the user can activate the weapon's special ability. The user gains a +2 enhancement to strength and constitution. An unlimited number of times per day (but only while this ability is active) the user can channel flesh to stone as a touch spell through the blade as a standard action. If you hit the opponent's touch AC but miss their total AC you may still petrify them as per the spell. The DC is Constitution based. Activating this ability is a full round action that provokes attacks of opportunity, and it lasts a number of rounds equal to 3 plus the character's(new) constitution modifier. During the course of this ability, the character can activate any of his or her feats except for Combat Expertise or Item Creation feats, and cannot cast spells or activate magic devices.