When the evil Doctor Ferrara revealed his other appearance, Cryogonal Man, he released a Poké Ball. Iris feared that it was a Cryogonal, but it was really a Vanillish.
Vanillish and Accelgor both battled hard, but Vanillish lost to Accelgor and fainted.
Ferrara said that he had a Vanillish, and that he wanted to have a Cryogonal but never had the strength to catch it. Iris points out that he's just a kid.