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From Pathfinder Treasure Vault (Remastered), which isn't enabled.

Viper Rapier

ITEM 20
Price 70000 gp
Usage held in 1 hand
Bulk 1
Category martial
Group sword
Damage 1d6 piercing

Crafted from flawless jade, the guard of this rapier takes the form of a twisting serpent with the blade thrusting from its open mouth. This rapier functions as a +3 greater striking quickstrike rapier. While wielding the rapier, your movement doesn't trigger reactions when you Stride, Balance, or Tumble Through. When you invest the rapier, you either increase your Dexterity modifier by 1 or increase it to +4, whichever would give you a higher value.

Activate (concentrate)
Frequency once per day
Trigger You fail, but don't critically fail, an attack using the viper rapier

Effect The tip of the rapier briefly takes the form of a viper's head, and the blade twists and contorts, biting the target you missed. The target is affected as if successfully poisoned with cave worm venom (DC 43).

Activate (concentrate)
Trigger A creature misses or critically misses you with an attack

Effect With a slight, obviously mocking bow or curtsy, you Step.

Activate (manipulate)
Frequency once per hour

Effect You twirl your rapier in a serpentine pattern, causing your form to become a blur of motion. You're Concealed for 1 minute or until you take a hostile action. While you're concealed, you also gain a +2 circumstance bonus to Reflex saving throws.

Effect: Viper Rapier

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