The Loonatics have been appointed “Guardians of the Universe”, as they relocate their headquarters to Planet Blanc, where they travel to dimensions in the flesh, as they find themselves in battle with the Martian Empire.
- Ace Bunny (Charlie Schlatter)
- Lexi Bunny (Jessica DiCicco)
- Danger Duck (Jason Marsden) - quits the Loonatics due to being always unappreciated for a 5-Episode arc that involves him becoming a solo hero working for the The United Galaxies as Duck Dangers, as he also finds himself facing Queen S'Duca
- Slam Tasmanian (Kevin Michael Richardson)
- Tech E. Coyote (Kevin Michael Richardson)
- Rev Runner (Rob Paulson)
- Speedy Gonzales Jr. (Carlos Alazraqui) - the Blue Loonatic and the descendent of Speedy Gonzaeles
- Martian Empire:
- Martian Queen S'Duca (Gabriel Union) - the main antagonist and the mother of Marvin the Martian, she is the Queen of the Martian Empire, as she makes it her goal to avenge her son's failure and destroy all who stand in her way.
- Iron Bull (Michael Dorn) - the Descendent of the Bull, a Minotaur that is the champion of the Queen's coliseum.
- Red Siren (Grey Griffin) - the Descendent of Red Hot Riding Hood, a singer with a voice to seduce any man.
- Which (Russi Taylor) - the Descendent of Witch Hazel, She plans to take Lexi's power to complete her magic.
- Massive (Issac Singleton Jr., replaces Michael Clarke Duncan) - plans to take revenge on the Loonatics to fulfill his debt with Iron Bull.
- Electro J. Fudd (Billy West) - ???
- Black Velvet (Vivica A. Fox) - ???
- Adolpho (Mark Hamill) - ???
The season runs for 19 Episodes.