Stink Potion

You throw it, it bursts on a solid surface, and everything inside a wide circle turns green and starts fuming. That includes you, anyone playing with you, the critters and the town residents, not only enemies. The debuff itself does no damage at all. What it does is send NPCs running and drag your luck down for the duration, which is the last thing you want while fishing or grinding a rare drop.

Almost never near your own base. As a prank in multiplayer it works exactly as advertised, and it will clear a room of villagers without you having to touch their housing. Beyond that there is not much reason to carry one, and there is a real reason not to throw it at your own feet before a long grind.