4. Air plane crossover. The corridor opens up suddenly into a vast open space, where blue sky appears to be all around – including below. A breach into the elemental plane of air, perhaps? There is another doorway level with the first, about 50’ away, and no immediately obvious way to get there. There is a tremendous wind upwelling from below, and anyone who asks – and makes a Perception DC 12 check – realizes that the air is strong enough to support them on their bellies to float to the other side. An Athletics or Acrobatics check is needed to progress every 10’, and a max of 10’ per round. When the first PC makes it over halfway across, the party is set upon by two air mephits that blended almost perfectly into the blue sky. If a character tries to cross wearing heavy armor, they find themselves too heavy to fully float, and they sink 1’ per round, potentially becoming lost forever if they are not rescued soon. This possibility can be recognized with a Perception DC 12 check, again.
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