
Synopsis
The Guardians must face an old enemy of Kandrakar – Nerissa Crossnic, the corrupted ex-Guardian and the previous Keeper of the Heart. When the Oracle realized how the immense power of the Heart was corrupting Nerissa, he took it away from her and gave it to Cassidy, the former Guardian of Water. Obsessed with her lost power and blinded by jealousy, Nerissa tricked Cassidy and killed her. As punishment, Nerissa was stripped of her magic and sentenced to sleep in Mount Thanos.

With the Heart now corrupted by Nerissa’s hatred, the former Guardian and her Knights of Vengeance attacked Kandrakar. Will later acquired the Star of Cassidy, a copy of the Heart from Cassidy’s ghost. With it, Will and her friends faced Nerissa in Kandrakar. In the final battle, Nerissa was killed by the Guardians. Despite their victory, Cornelia is heart-broken when Caleb left her due to their complicated relationship and him realizing her true age.