Howling Mine

A stone arch, carved to resemble the screaming mouth of some enormous beast. Only darkness can be seen beyond it, and a powerful wind constantly blows from it, hot and wet, accompanied by a subdued but ever present shriek. The other side of the arch, if visible, looks exactly the same, with the same effect. Each creature in a 120-foot long cone originating from the entrance of the mine on either side may take an additional action on each of their turns. Whenever a creature does so, they must make a DC 15 Constitution saving throw or suffer one level of exhaustion. A creature attempting to enter the mine or shove another creature into the entrance must make a DC 25 Strength saving throw, or be pushed 15 feet backwards by a powerful gust of wind. If a creature pushed in this way strikes an object or another creature, both take 2d8 bludgeoning damage. Objects may be thrown into the entrance of the mine with no difficulty. Any creature or object which passes beyond the arch that marks the entrance of the mine is immediately transported to a random plane (determined by the DM) by way of the Astral Plane, in a process which stretches and distorts time and space, causing the creature or object to take 6d6 bludgeoning damage and 6d6 necrotic damage.