Ranger Trap: Miasma

Prerequisite: 5th-level ranger; magical

When activated, a 20-foot-radius sphere centered on the trap fills with gas for the next minute or until strong wind disperses it. The gas spreads around corners, lightly obscures the area, and penetrates through creatures' skin, affecting them even if they hold their breath or don't need to breathe. When a creature enters the area for the first time on its turn or starts its turn there, it must make a Constitution saving throw. On a failure, a creature takes 3d6 poison damage and becomes poisoned until the start of its next turn. On a success, a creature takes half as much damage and isn't poisoned. While poisoned in this way, a creature has disadvantage on saving throws it makes to maintain its concentration.