A potion made from the essences in Roper Klacks' laboratory. This potion, like the Explosive Potion, is not designed to be drunk by the user. It summons or releases the winds when thrown into the air, or simply calls up a brief gust when the vial is opened. When April mixed it at the top of the floating castle, she asked Crow to throw it into the air for her, releasing the winds Roper Klacks had captured with magic.
When April spoke to Captain Horatio Nebevay back in Marcuria, Nebevay was still reluctant to let her aboard the White Dragon due to his superstitions regarding women. However, when he saw just how powerful the wind potion was, he changed his mind very quickly. Presumably, once she was on board, April used the potion's magic to speed them on their way. When the Chaos Storm erupted and Nebevay changed course, refusing to risk his crew's life to go to Alais, April threatened to stop using the potion but Nebevay pointed out the headwind from the Storm was much more powerful.
There was still a little of the potion left by the time April arrived on Alais. She used the last of it to increase the winds blowing through the chasm on the way to Tama'a, the Alatien village, then drank the Light-As-A-Leaf Potion, using the strong winds to 'fly' across. This convinced Isaam, the Alatien on guard, that April was the Windbringer. This title refers to a human who can fly without wings; however, given her frequent use of the Wind Potion, it is a good name for April.
Mixed in Roper Klacks' laboratory.