Gas Trap

There is no recipe. Take a Whoopie Cushion, throw it into Shimmer, and it comes back as this. Worlds running the No Traps seed hand them out the other way around, seeding them straight into ordinary chest loot, which is the joke that seed is built on.

Drop one inside a chest or any other container that is placed in the world, then walk away. The next person to open that container sets it off. Portable storage does nothing at all, since the trap needs a container that exists as a tile.

• Stacking several in one chest is wasted effort. Only a single one fires per opening, so spreading them across separate chests catches more people.
• Testing it alone can mislead you. With autopause switched on in singleplayer the trap simply refuses to trigger, which reads as a broken item rather than a setting.

When it goes off, a gas cloud swells out from the chest almost instantly, hangs there for about a second, then fades. Everything caught inside comes out poisoned. It does not care who opened the lid, so town NPCs nearby and any other player in the room get dosed alongside the victim. The cloud borrows its look and behavior from the Toxic Flask, a fair guide to how much ground it covers.

Afterward the item degrades into a Used Gas Trap, which is completely inert and cannot be armed again on its own. Shimmer restores it, so one trap can be recycled indefinitely as long as you keep access to a pool.