|[List of appearances]|
Rufus McCallister, better known as "Mother Doomsday", is the owner of the "Ninjago Doomsday Comix" shop. He was first shown in the Ninjago: Masters of Spinjitzu show before appearing in 2017's 70620 Ninjago City.
When the ninja were accidentally turned into children and being hunted by the Grundal, Lloyd decided to ask Mother Doomsday for help defeating it. Although he thought they were only talking to him about a theoretical situation, he gave them information about the Grundal's strengths and weaknesses. When mentioning that a Grundal could perhaps be defeated with the illuma-swords, he then told the ninja they could have them if they won the upcoming trivia contest hosted by him, in which the swords were the prize. He was in the store when the Grundal attacked, and he and the other children were trapped until Sensei Wu and Nya came and helped them while delivering the tea the ninjas needed to turn the clock forwards and grow older again. After the Grundal was defeated, he offered Lloyd a comic book of Star Fared, saying he earned it, but Lloyd said he already knew how it ended. Rufus also appeared in The Day Ninjago Stood Still being chased out of his shop by a Stone Warrior and tried to fight him with a toy sword but ran out again holding his comics. His last appearance to date was in The Last Voyage when he was talking to Zane.