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From Pathfinder Lost Omens High Seas, which isn't enabled.

Sanguine Ammunition

ITEM 8
Price 75 gp
Bulk L

Ammunition any

Activate (manipulate)

This wickedly barbed ammunition looks dangerous to even touch. It dissolves into blood on impact, leaving no trace if the target has blood. The target takes a –2 circumstance penalty to saves against diseases and poisons for 1 round.

You can also Activate sanguine ammunition as part of Casting a Spell. The spell must be 3rd-rank or lower, must take 1 or 2 actions to cast, must have the poison or disease trait, and must target a creature other than the caster. Casting a Spell this way has no effect; instead, a creature hit by sanguine ammunition activated this way is targeted by the spell in addition to the item's normal effects. If the target isn't a valid target for the spell, the spell is lost.

The ammunition affects only the target hit. If the spell requires a spell attack, use the result of your ranged attack roll to determine the degree of success of the spell. If the spell requires a save, the target attempts the save against your spell DC.

Pathfinder Lost Omens High SeasORC