Here are the characters who've been revealed so far, along with the voice actors portraying them in the animated short. (If no voice actor is listed, it means that this character either does not appear in the short (but may appear in the eventual series and/or comic), or has a nonspeaking background role in the short (but may have a larger role in the series and/or comic).)
I intend to add a new character every Monday night. However, I've been intending to do that for a long time, and haven't always done that, so, uh, don't be surprised if it doesn't always happen. I'll try, though.
Branton Mongley | 
Clio Mongley | 
Niamh Mongley | 
Wade Mongley |
Tapper Xug | 
Dianne Xug | 
Connie Xug | 
Junji Amigara |
Mrs. Furk | 
Francine Glabergood | 
Tabitha Forthright | 
Theretta Belwin |
Jag Tallerson | 
Skyla Bernard | 
Dr. Werner Loregaard | 
Hermina Rathwittle |
Z | 
Sean Xug | 
Nirelda Varane | 
Gulliver Oin |
Darryll Mudroe | 
Garlock Walters | 
Mylene Batters | 
Toby Wallawey |
Tomi Amigara | 
Roshambo | 
~!@~ Xug | 
Incarnadine Glorch |
Maura Tregane | 
Yok | 
Vjulo Dupree | 
Valoria Gribbon |
Abraham Collado | 
Ptolemy Brown | 
Nicole Frissman | 
Dale Wintergreen |
Cherryl Dunn | 
Melodica Bing | 
Dr. Theseus Ordanis | 
Pete Cranshaw |
Wallacia Turnbridge | 
Orland Gelger | 
Sharon Crundle | 
Wilbur "Gramps" Gorbuckle |
Risetta Thune | 
Vasco Galduria | 
Ermintrude Spinglestock | 
Qquuq |
Michael "DJ MixMike" Mackowitz | 
Lulu and Mimi Vrallon | 
Delinda East | 
Natalie Morez |
Xandra Blair | 
Winifred "Winnie" Lovewort | 
Griseldine Lippencott | 
Salmonella Wetherwood |
Wilhelmina | 
Mrs. Kim | 
Gomorrah Jade | 
Daramone Derayne |
Ursula Xant | 
Chance Alfridge | 
Magenta Gray | 
Daisy Daffodill |
Bunches | 
Rutherford Lund | 
Pomona Dietz | 
Charles Meddingway |
Aurora Wing | 
Dexter Wedebi | 
Eustace Blint | 
Kayla Worthingdale |
Lucinda Wei | 
Dr. Zarna Zarekar | 
Lou Cankerelli | 
Rupert and Hepzibah Middleboroughleigh |
Lionel Watson | 
Fiona Snabblejax | 
Olo | 
Jameson Thwark |
Lilian MacGander | 
Perry Lee | 
Nid | 
Logan Ward |
Lwcwm | 
Ramiro Adelar | 
Beauregard Fruge | 
Doris Polkerson |
Waranda, Maximus, and Cole | 
Nima Yuseidi | 
The Spinglestock Twins | 
Macy Toblone |
Hagar Margolis | 
Eunice Mulvaney | 
Simon Martermold | 
Flop |
Paprika Sambara | 
Leonard Barnum | 
Aunt Lake | 
Noelle Zark |
Anathème Tresbeau | 
Debbie Valero | 
P* | 
Etchy |
Druce | 
Anthony and Morgana Belwin | 
Isabel Vinh | 
Gerónimo "Harry" Bazán |
Beryl Warabe | 
Vorbulox the All-Powerful | 
Calliope Horn | 
Kharisma Kane |
Helga Pfeffunkel | 
Maynard Gabbaline | 
Dr. Ariel | 
Green Square Person |
Miyuki Zord | 
Raul Duhagon | 
Remmie Kazar | 
Kimiko Amigara |
Angelica Ropp | 
Hexacritha "Hex" Bogomilj | 
Pimbleton Prupp | 
Raine Scorgum |
Squalter Milson | 
The Howling of the Breach | 
Mr. Orm | 
Diggory Gual |
Dhragada "Gad" Vrad | 
Lizzie Burkalter | 
Peregrine | 
Yntonio Phrogg |
Milgreg Borgleson | 
Egremia Plumm | 
Salydia Lahar | 
Hildegard Gardener |
Nivloch the Denier | 
Portento the Great | 
Metonymy | 
Renona Borke |
Marquessa Wildebrandt | 
Fginniman Gmort | 
Eslagar the Wise | 
Millicene Rutelmeier |