|Occupation||Leader of the Fungi|
|Voiced by||Christopher Gaze|
| Barbie Fairytopia: Mermaidia |
Barbie Fairytopia: Magic of the Rainbow
Barbie Fairytopia: Mermaidia is where he first appears, as the leader of the Fungi. He threatens to pour a bottle of magical poison into the ocean to destroy Mermaidia if Prince Nalu does not lead them to the immunity berry.
In Barbie Fairytopia: Magic of the Rainbow, he stalks Azura and later Elina under Laverna's orders. He is later turned into a toad to stand in for Laverna, so the guardians think she is still in exile.
Fungus Maximus has dark green skin and hazel eyes. He wears a purple suit, a gold ring with a purple gem on his left middle finger, and has many warts on his face. His ears are pointed and his nose takes up most of his face.
Quotes: "What makes you different makes you special." | "Trust your true self." | "Together we're strong"
Characters: Amethyst | Azura | Bibble | Dahlia | Delphine | Dizzle | Elina | Enchantress | Faban | Fungus Maximus | Guardians of Fairytopia | Glee | Happy Trolls | Hue | Larkspur | Laverna | Linden | Lumina | Nori | Pixie | Prince Nalu | Quill | Ruby | Sea Butterfly | Yellow Merfairy | Wise Fish | Shellie | Delphine | Teeny Mermaid | Purple Merfairy | Pink Merfairy | Shimmer | Sunburst | Topaz | Tourmaline
Songs: "I'm Flying" | "The Friends You Haven't Met" | "Laverna's Formula" | "Goin' to Azura's Cottage" |"A Rainbow In Your Eyes" | "Rise Above It All" | "Laverna's Checklist" | "Stay Awhile" | "The Friends You Haven't Met (Reprise)" | "Goin' to Laverna's Castle" | "Azura's Necklace" | "Laverna's Exit" | "I'm Flying (Reprise)" | "Rise Above It All (Dance Mix)"