When Halo teams up with Flora Fawn to write a report on ways to reduce pollution, the cheating, littering Doozie Hiss enrages Flora, who turns into the formidable Green Queen, forcing Halo to use her superpowers to rescue Doozie.
Echo, a shapeshifter, steals Halo Nightly's magic candy to become her evil twin and keep her from being friends with Cody Phinn, until Halo turns herself into the Ice Princess.