- Scott Adsit as Baymax
- Ryan Potter as Hiro Hamada
- Brooks Wheelan as Fred
- Jamie Chung as Go Go Tomago
- Khary Payton as Wasabi
- Génesis Rodríguez as Honey Lemon
- Mara Wilson as Liv Amara
- Dee Bradley Baker as Mayoi
- Diedrich Bader as Bluff Dunder, Felony Carl
- Ben Feldman as Chris
- John Michael Higgins as Mini-Max, Civilian
- Jenifer Lewis as Professor Granville
- Lucas Neff as Noodle Burger Boy, Fanboy
- Patton Oswalt as Mr. Sparkles
- Christy Carlson Romano as Trina
- Maya Rudolph as Aunt Cass, Old Lady
- Haley Tju as Karmi, Small Child
- Alan Tudyk as Alistair Krei
- Mayoi is the Japanese word for "doubt", "hesitation", and "bewilderment". When written in kanji, Mayoi contains 迷い, while "迷" refers to "lost". This could be in reference to their role in presenting Sycorax as an ally to San Fransokyo.
- This episode may be a reference to the 1984 film, Gremlins.
- This is the first episode in which Bluff Dunder directly interacts with one of the Big Hero 6, in this case Hiro whom he pokes fun at for being short.