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From Pathfinder Impossible Magic, which isn't enabled.

Magekiller Bullet

ITEM 16
Price 1500 gp
Bulk L

Ammunition round or sling bullet

Activate (manipulate)

Magekiller bullets are forged by carving a spellcaster's bones with sigils of unbinding, grinding them to powder, and sealing the powder within the core of specially made rounds or sling bullets. When an activated magekiller bullet hits a target, the ammunition burrows deep into its body and interferes with its connection to magic.

Each time within the next week an affected target Casts a Spell, it must attempt a DC 11 flat check. On a failure, it takes 2d12 force damage. This curse can be counteracted with cleanse affliction as normal, but if the ammunition is first removed from the target with a successful DC 35 Medicine check and an operation that takes 1 hour, the counteract check gains a +4 circumstance bonus.

Pathfinder Impossible MagicORC