Oil of Deep Slumber
Potion,
Very Rare
(cost 6500 gp)
Crafting Components
Ground moonstone
You can spend 1 minute applying this midnight-blue oil flecked with silver to 5 pieces of piercing ammunition. For the next hour, the coated ammunition is magical and can put creatures hit by it to sleep. When a coated piece of ammunition deals damage to a creature with 100 or fewer hit points, the creature instantly falls unconscious .
The creature remains unconscious for 3d6 minutes or until it takes damage.
Source