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From Pathfinder #203: Shepherd of Decay, which isn't enabled.

Boughshatter

ITEM 13
UNCOMMONEARTHMAGICALPOISONVERSATILE-P
Price 2875 gp
Usage held in 1 hand
Bulk 1
Category simple
Group club
Damage 1d6 bludgeoning

The spikes of this +2 greater striking standard-grade adamantine morningstar have a faintly green shimmer, as if resembling Ayrzul's crystalline teeth. The weapon vibrates briefly when first drawn in or carried into a radioactive area, with the intensity of the vibration correlating to the radioactivity's strength. While you carry Boughshatter, you gain a +4 status bonus to saving throws against radiation, including Ayrzul's Blight.

Activate—Splintering Strike (manipulate)
Frequency Once per minute
Effect Make a Strike with the morningstar that deals an extra die of weapon damage. If you make this Strike against a fungus, plant, or creature with the wood trait, the Strike ignores 10 points of the target's resistances to bludgeoning and piercing damage, if any. By damaging such a creature, the morningstar causes the target's flesh to explode in a shower of splinters that affect a 30-foot cone originating from the target's space, dealing 8d6 piercing damage to creatures in the area (DC 30 basic Reflex save). You and the target are unaffected by these splinters.
Activate—Absorb Corruption (concentrate)
Frequency Once per day
Trigger You take poison or void damage;
Effect You channel some of the toxic energy into Boughshatter, granting the weapon the effects of either a Decaying weapon rune, Grievous weapon rune, or Wounding weapon rune for 1 minute. While under this effect, the morningstar glows with dim green light in a 20-foot radius.
Pathfinder #203: Shepherd of DecayORC