When Bowser does what should never be done to Mario (turning his spaghetti upside down on the floor), Mario assembles his friends together and creates the Mario Mafia to track him down.
Mario and Meggy are training hard for the new splatfest when a particular Octoling crashes their party... will the two become friends with the newcomer? Or will she end up breaking their friendship?
Fishy Boopkins wants to get accepted in to Tennis Aces, but he needs to know how to play first, and so Mario (Who is now in a wheelchair because he got into a tennis accident) gives him some pointers.
SMG4 is completely broke due to buying more rocks than he can afford, and now his last hope for getting out of debt rests with his friends being able to sell the aforementioned rocks.
Waluigi wants to be put in Super Smash Bros., but when he is told by Master Hand he is not unique enough because he has no special move, Waluigi embarks on a journey to find his own special move.
A normal day becomes an apocalyptic day when Mario and friends become slowly overwhelmed by a massive horde of SMG4 characters turned into T-Pose Zombies.
Mario is forced to replace Toadsworth's new painting after using it to unclog the overflowing toilet, otherwise Toadsworth will kill(?) Mario's Spaghetti.
Mario is completely fed up with losing to SMG4 in Super Smash Each Other in the Ass Brothers, and so, after seeing a blue-haired girl beat Bob in the same game at the Mall, Mario begs the girl, named Tari, to train him.
Mario and Luigi wake up to find themselves chained inside a bathroom with Piranha Plants clasped on their heads, and a masked figure on a television sends them through this and other death traps.
Following the events of "Mario SAW", Wario finds Mario still strapped in the chair from the end of the aforementioned story, and, because he has not seen Waluigi since "Waluigi's Time", he decides to have Mario become his new scam partner.
Due to Waluigi taking over the remnants of the Mushroom Kingdoms with his T-Pose army, Mario and SMG4 embark on a mission to go back to the convention and save their friends.
The final showdown of Mario and SMG4 versus Waluigi is soon - But first, they will have to compete against one another in several WOTFI challenges for Waluigi's enjoyment.
When Bob comes to the castle seeking shelter from the annual Teletubbie purge, SMG4 and others are hesitant to let him in, and the only one who does let him in is Fishy Boopkins, not knowing what he has unleashed upon the castle.
When Mario finds out that SMG3 is responsible for an internet drought, he tries to get help from his friends, who have mostly gone crazy from lack of internet.
Mario and Luigi are "hired" by Bob to help him manage his rap tour. Meanwhile, Bob forbids Boopkins from coming with him for a currently unknown reason.
SMG4, Mario, and Tari camp outside the mall in order to get their hands on a copy of the new Super Smash Each Other In The Ass Brothers game that seemingly everybody wants, but a certain bunch of Koopalings want a copy too.
