Eternal Pipe

This intricately wrought pipe portrays a fanciful sculpture of some mythological beast. Even when it sits quietly it emits light wisps of smoke.
Benefit: By blowing out rings of smoke from the Eternal Pipe, you can create several thick clouds that hover persistently once placed. As part of a move action, if you do not have 3 or more active clouds, you may create a single cloud in an unoccupied target square within [Close] range, which lasts and remains active for five [Rounds] or until it is destroyed. Each cloud is an obstacle that occupies one square and possesses 45 hit points. Each cloud may be treated as a creature for the purposes of targeting with attacks and effects that deal damage and for the purposes of area effects that deal damage. Each cloud cannot make saving throws and is hit by any attacks targeting it. If an effect would damage a cloud on the cloud’s turn, it is damaged on your turn. Once a cloud reaches 0 or fewer hit points, it is destroyed.

As part of a move action used for movement, a creature may make a DC 15 Athletics check. Success means the creature can climb over the clouds, allowing it to enter and leave squares the clouds occupy as if they were not obstacles for one [Round]; failure means they cannot enter those squares for that movement.