watch 01:24 The Loop (TV) Do you like this video? Manacle-Os is a brand of cereal that appears in "The Secret Origin of Supernova." They are themed around Manacle. Arthur wants to buy a box, but he decides against it after his dad tells him how sugary and unhealthy the cereal is. Retrieved from "https://arthur.fandom.com/wiki/Manacle-Os?oldid=385860" Categories: Objects Foods and drinks A to Z Community content is available under CC-BY-SA unless otherwise noted.