Elixir of Gaseous Form
When you drink this elixir, you feel momentarily lightheaded as your body fades to vapor.
Consumable: Elixir 500 gp
Utility Power (Polymorph) Consumable (Minor Action)
Effect: You drink the elixir and take on the form of a misty cloud until the end of the encounter or until you end the effect as a standard action. All your gear is absorbed into your gaseous form and is inaccessible. While gaseous, you are insubstantial and gain a fly speed equal to your speed, as well as the ability to hover. You cannot make attacks while in gaseous form, but you can move unhindered through tiny openings that would otherwise prevent movement (such as under a door or through a cracked window).
Published in Mordenkainen's Magnificent Emporium, page(s) 92.