Yume Kōjō: Doki Doki Panic
The "Muu" first appear in Yume Kōjō: Doki Doki Panic, the game upon which Super Mario Bros. 2 is based. In this appearance, they are fictional characters in the tale of the world of dreams, Muu Kai. The happy Muu people lived peaceful lives in a land where the weather is decided by the "dream of the day": if everyone has a nice dream, then the weather is bright and sunny, but if everyone has a bad dream, then the weather becomes stormy. The Muu invented the Dream Machine, so they could always have good dreams and good weather, but a mischievous monster named Mamu changed the machine to produce monsters. However, Mamu was weak to vegetables and hated them more than anything in the world. The Muu fought Mamu by hurling vegetables at him until he was buried. Mamu surrendered and peace was restored to their world.
The story would have ended there had the "real life" twins Poki & Piki not squabbled over the storybook presented by Rūsa the monkey. They fought over the last page and accidentally tore out the book's ending. In a flash, Mamu sticks his hand through the pages of the storybook and kidnaps the two children, pulling them through the book and imprisoning them within a cage near the Muu people. This allowed Mamu to conquer the dream world. Luckily, Rūsa alerted the family consisting of Papa, Mama, and their son, Imajin along with Imajin's girlfriend Lina. They hopped into the storybook to save the children, each progressing through the story at their own pace. In the end, after defeating the armies and their bosses, the four defeat the diabolical monster and free the Muu from Mamu's jar, thus restoring a happy ending. With the citizens rescued and the storyline fixed, the world they inhabit and the kidnapped children are rescued as well, and the six return to the real world.
Super Mario Bros. 2
In Super Mario Bros. 2, the evil tyrant Wart mysteriously appears and takes over the land of Subcon and imprisons the Subcon people in a jar. For their last hope, the Subcons contact the great hero of the Mushroom Kingdom, Mario, in his sleep to ask for his help. They also give him a hint to beat Wart, which is his distaste for vegetables. Mario, believing the message to be nothing more than a dream, dismisses it and later goes on a picnic to the park with Luigi, Toad, and Princess Toadstool. Mario then discovers a door in a cave leading to Subcon. Realizing that there may be some truth to his dream, Mario and his companions embark on a quest to save the dream people. After Wart is defeated, the people are released. They pick up Wart's battered body and carry it off-screen (with various swirls emerging from the screen implying that they gave the evil frog another beating), leaving his fate unknown until the pseudo-sequel, BS Super Mario USA, reveals that he and his crew escaped to another dream world. They eventually return, but the king of Subcon uses the power of the stars to summon Mario and the others once more.
Subcon first appeared in Super Mario Bros. 2, where they are inhabitants and loyal servants of the world's king (only seen in BS Super Mario USA). They are also known to protect the dream world and its kingdom. However, they are imprisoned by Wart and his crew, the 8 bits, and one of them is even enslaved.
All Subcons wear red or pink pajama-like clothing. They have black or teal hair and are able to fly using their wings, resembling Beezos.
Traits and abilities
The Subcons are capable of speech. They can contact others through their subconscious, as is done with Mario. Despite being capable of protecting the dream world and the kingdom, judging from physical appearance, the casual observer would regard them as physically weak.
Names in other languages