(Its been 12 straight days of horror since Kirby became plagued by this... infection, and killed Mario... ever since the Multiverse has fallen into chaos as the infected fighter run rampant throughout their perspective universes destroying all in their path)

(*At least some survived, like you, Ness, Cappy (Who once possessed Mario’s hat not possesses Ness' hat), Sheik, Marth (Whos arm had to be amputated due to the virus) and Villager all were staying in a safe base with Dr. Mario, researching the virus to know morr and possible for a cure to this damned virus. R.O.B(who was damaged at the time) was helping him too, since the robot can't get infected, and Olimar's been the first infected to get (willingly) researched on, but he became too dangerous and got killed by R.O.B while infected Pikmins were eating the astronauts from the inside out)

(*Then there's the deceased: the original Mario had fallen victim to Kirby, Luigi, Yoshi, Peach, And Daisy died to The monstrosity that once was Piranha Plant and poor Snake drowned in the sea by the inkling siblings... their could be many more that just that)

(the infected fighters you've seen are even worse... Kirby just infecting everything in his path, but contained in Dreamland... Mr. Game & Watch turned into a three-dimensional, lanky monster, Piranha Plant was now a kaiju abomination, Inkling Girl became a giant monstrous squid, and god knows who else suffered this infection)

(Luckily, most of the infected are all confined to their original universes, meaning they couldn't harm anyone outside of them. You all tried looking for Master Hand and Crazy Hand too, hoping they could help in fixing this, but to no avail. And now, after Mewtwo and Mii Sword-Fighter infected by Pichu and Dr. Mario seemingly sacrificed himself in his safe base to let you all escape as he maybe died and Pit hasn’t been seen in awhile many of you don't know what to do anymore)

(Eventually though, you all make it to the Animal Crossing Universe to regroup.)