pf2e.fyi
From Pathfinder Treasure Vault (Remastered), which isn't enabled.

Nightpitch

ITEM 5
CATALYSTCONSUMABLEMAGICAL
Price 60 gp
Usage held in 1 hand
Bulk L
Category catalyst
Activate Cast a Spell

A pellet of tar mixed with the fur of a nocturnal creature, such as a bat, nightpitch used to cast a Darkness spell makes the area of the darkness difficult terrain.

Pathfinder Treasure Vault (Remastered)ORC