Here is another installment of exTRAPaganza, our Thursday over-the-top trap series.
It is rumored that gold and magical treasure beyond measure lies under the swamp.
The swamp contains plants that emit an odorless gas that adheres to the adventurers. Outside, it is harmless, but once the caverns under the swamps are entered, it becomes potent. While in the caverns, the scent from the swamp stays on the party for 2d6 hours. During this time, it attracts all manner of insects, bugs and vermin. Any single insect, but or vermin encounter automatically draws an additional 1d4 swarms of the same type.