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From Pathfinder War of Immortals, which isn't enabled.

Shadowpiercer

ITEM 23
UNIQUEARTIFACTMAGICALMONKMYTHICTHROWN-20
Usage held in 1 hand
Bulk 1
Category simple
Group spear
Damage 1d6 piercing

Muted, silvery moonlight gleams along the curved blade of this +4 major striking ghost touch spear. Braided tassels of horsehair dangle from its sturdy haft, and archaic runes in Nidalese script shimmer along the weapon in the presence of shadow magic.

Shadowpiercer ignores immunity and resistance to precision damage of creatures with the incorporeal or shadow trait, and deals an additional 2d6 precision damage to such creatures. While wielding Shadowpiercer, you gain a +2 status bonus to saving throws against darkness and shadow effects; this bonus also applies to allies within 60 feet of you while you wield the spear. If you are a worshipper of Zon-Kuthon, you are Drained 4 and Enfeebled 4 while carrying or wielding Shadowpiercer. If you use a darkness or shadow effect while carrying or wielding Shadowpiercer, you become enfeebled 4; this condition's value reduces by 1 at the start of each day you do not have physical contact with Shadowpiercer.

Activate—Absorb Shadows (concentrate, healing, manipulate, occult)
Frequency once per day
Effect You touch Shadowpiercer to a darkness or shadow effect to siphon its energy and bolster yourself. You gain a number of temporary Hit Points equal to four times the effect's counteract rank. These temporary Hit Points last for 1 hour. In addition, if the effect is causing darkness, that darkness is automatically counteracted within 15 feet of you for as long as you have those temporary Hit Points. This doesn't provide light—it merely restores the area to its natural illumination level.
Activate—Rebuff Gloom (concentrate, occult)
Trigger You or an ally within 60 feet is targeted by a darkness or shadow effect
Requirements You don't currently have the drained condition
Effect Spend a Mythic Point; the spear drains your vitality to counteract the effect. You can attempt to counteract the effect (+46 modifier level, counteract rank 10). You can activate this effect without having a Mythic Point available but doing so makes you Drained 2.

Destruction Shadowpiercer simply disappears if a worshipper of Zon-Kuthon casts a 10th-rank Darkness spell on it once a day for an entire month while it is unattended.

Pathfinder War of ImmortalsORC