Creatures that start their turn or move within 5 feet of the swamp troll must succeed on a DC 15 Constitution saving throw or become poisoned. The creature can repeat the saving throw at the start of each of their turns, ending the effect on itself on a success. If the creature stays at least 10 feet away from the swamp troll for an entire round they automatically succeed on saving throws to end the effect. After a successful saving throw, a creature is immune to the swamp troll's stench for 24 hours.