pf2e.fyi
From Pathfinder Impossible Magic, which isn't enabled.

Chatterer of Follies

ITEM 6
UNCOMMONILLUSIONMAGICALMENTALSHOVETWO-HAND-D10VERSATILE-P
Price 200 gp
Usage held in 1 hand
Bulk 1
Category martial
Group club
Damage 1d6 bludgeoning

This heavy +1 striking khakkara is cast from solid steel and plated with pyrite. Metal charms shaped like grinning idols festoon its great arched ring, and during combat, these hanging dolls seem to chatter in tune with the clash and din of battle. Any time you cast an illusion or mental spell while wielding this weapon, you become Concealed until the end of the turn.

Activate—Confounding Chatter (concentrate)
Frequency once per round
Requirements Your last action was a move action
Effect The idols gibber at a nearby foe. Choose an adjacent creature. Until the end of your turn, that creature takes a –1 status penalty to Will saves against your illusion and mental spells.

Effect: Chatterer of Follies

Pathfinder Impossible MagicORC