Super Mario Maker: Crash Course
Super Mario Maker: Crash Course was a feature on the official website for Super Mario Maker, though the site is currently down as of May 24, 2019. In it, Yamamura teaches Mary O. how to improve upon her level design philosophy by creating better Mario levels.
As Mary O. and Yamamura reflect on the success of Super Mario Maker (two million levels uploaded to Course World as of October 2015), Mary O. suddenly realizes that she has a level of her own. When Yamamura plays said level, he is instantly flabbergasted at how objectively poor the level's design is, citing the Thwomps stationed above the screen, Lava Bubbles placed in random locations, and the fact that there are simply too many enemies. Yamamura decides to teach Mary O. the basics of level creation, and challenges her to create a level with only the elements available from the start of the game and with no vertical scrolling, to which she accepts.
As Yamamura looks over the level Mary O. submitted, he surmises that the level is good for a start, and highlights that the limitations helped Mary O. understand the importance of placement. After pointing out how the Big Goomba close to the Goal Pole in his own level is "fun" to stomp on, Yamamura challenges Mary O. to create a "satisfying" level with the same limitations as before, to which she obliges.
Mary O. submits her "satisfying" level assignment to Yamamura. As Yamamura proceeds to make his own changes to the level, Mary O. realizes that his version is nearly identical to hers, and moreover, that she passed her assignment. Yamamura stated that she had learned about creating moments of both tension and elation when creating said level, and that she had already passed. After stating that he had hid the Super Star at the beginning in a Hidden Block to not make it the "intended" way to play, Yamamura talks about satisfaction of small victories, as well as shortening a pit for reasons he would go into later. Noting that there is nothing interesting about the level as a whole, Yamamura challenges Mary O. to create a "memorable" level with vertical scrolling permitted but still with not too many elements, to which she again obliges.
Having finished her task from the previous episode, Mary O. explains to Yamamura what makes her level "memorable", using a wide variety of enemies and objects, placing Boos adjacent to Cloud Blocks, and adding Yoshi due to Mary O.'s incessant obsession of him. However, Yamamura rejects said level, citing a lack of cohesion as his main issue, and that the only good thing about it was the Boos near the Cloud Blocks, something he expanded on in his own level. Yamamura then goes on to state that he carefully designed his level so that the players would easily see the Boos, and goes on to explain that purpose, style, and functionality are what constitute good level design. Mary O. suddenly bemoans over the fact that Yoshi is nowhere to be seen in Yamamura's level, to which Yamamura explains that Yoshi is dysfunctional in the level due to his inability to eat Boos; however, the two realize that Mary O.'s next task would be creating a Yoshi-themed level, which Mary O. instantly accepts.
Mary O. is eager to see Yamamura test her latest task, revealing that she had utilized as many of Yoshi's abilities as possible. She also reveals that she had created alternate routes in the level of varying difficulties. While Yamamura admits that the level was fairly well designed aside from a shortage of enemies, one of the level's bigger problems was that some of the jumps and drops in the level were too risky for any normal player to attempt, something he fixed in his own level. He also reveals that he narrowed a gap in Episode 3's assignment so that the player could jump over it without dashing. With this in mind, Mary O. finally realizes the importance of considering other players' perspectives when creating a level. To test how far she has come, Yamamura tasks her in a level-creation challenge.
Bonus Episode 1
Yamamura wants to tell Mary O. how he feels after spending time creating courses with her. Mary O. is surprised and thinks that Yamamura is doing "a love confession." As Yamaura tells her that her final course "stole my heart" and is about to announce something, Mary O. shouts "I-I-I'M SO SORRY!!!!!" Yamamura is confused and explains that he was not "about to confess my undying pigeon love to you," and that the announcement is that Mary O. has been added as a costume. Mary O. is excited and wants to make a course using it, and Yamamura goes over the three course elements that had been added in the update: the Skewer, the Key and Key Door, and Pink Coins. He gives Mary O. a final homework assignment to make a course involving Key Doors, and she accepts.