Iggy is Sophie Foster's pet Imp. She rescued him from the Verminion (AKA Hamsterzilla) in Keeper of the Lost Cities. At first Grady protested to keeping Iggy because Imps can be troublesome (one destroyed his tree house) but he quickly gave in and let Sophie keep Iggy when he saw how much Sophie loved Iggy. Biana likes to keep Iggy at Everglen, and likes to give him makeovers, turning his fur different colors.
Iggy has black wings, green eyes, and gray fur.
In Exile, Dex gives Iggy an elixir, turning Iggy's fur pink and curly. Dex later turns Iggy's fur orange with dreadlocks during Everblaze, blue in Neverseen, purple in Lodestar, and green in Nightfall.
Iggy has famous "Iggy breath" which smells horrible. He likes to curl up with Sophie at night and play. One of his favorite places to be petted is his tummy. He enjoys playing with his pink curls.
During Book 1, Sophie learned to talk telepathically to Iggy and give him simple commands. Under Sophie's instruction, Iggy tried to help Sophie by biting the Neverseen agents who kidnapped her. Imp bites are venomous but not deadly, as Grady has stated.
In Lodestar, Iggy was turned purple and poofy by Dex.
- Iggy's "Purple Reign" is most likely a reference to Prince, with his famous song, "Purple Rain".