Persephone is a supporting protagonist of the Skylanders series. She aids the Skylanders by giving them upgrades.
Skylanders: Spyro's Adventure
Once the Skylander meets her in Sky Schooner Docks, she will return to the Ruins where she sets up her Upgrade shop. Players can earn up to 20% off the cost of character upgrades by finding Winged Sapphires hidden around the Ruins.
Persephone appeared in the sequel to Spyro's Adventure, continuing her role in offering the Skylanders to upgrade their abilites in exchange for treasure after stowing away on the Dread-Yacht. She has also improved her speech.
Skylanders: Swap Force
Persephone along with the other fairies are in charge of providing the trees of the Fairy Wood nourishment. During the story events of the game, she and her sisters were captured by Count Moneybone but were eventually freed by the Skylanders. After saving the Fairy Wood, Persephone went to Boom Town.
Skylanders: Trap Team
Persephone returns to provide her magic in upgrading the Skylanders. She has set up her house at the Skylanders Academy, and can be found in levels for the Skylanders to upgrade.
In the Mirror of Mystery realm, she is an evil fairy who loathes Skylanders.
Return of the Dragon King
During Malefor's attack on the Skylanders Academy, Persephone spotted Calliope hiding amist the crowd of spectators and scolded the fairy for misusing her magic to help Malefor. The Fairy Queen then persuaded Calliope that it wasn't too late to do the right thing, which resulted in Calliope aiding the Skylanders in defeating Malefor.