User blog comment:ChishioKunrin/Maidens - Origin of Dust and the Kingdoms?/@comment-226878-20151214053635

Maidens and Dust by color: Spring - Wind, Summer - Lightning, Autumn - Fire

Elementally speaking, this would explain why Conder uses fire as she stole Autumn's Aura.

As to Autumn being of Vale because of Forever Fall... Emerald Forest and the snowy fields where Summer's grave is found indicate other seasons are experienced in this realm.