"M", also known as "Horror Mario" or "Mario.EXE", is a sadistic, malevolent and twisted entity that stalks video games, originally teaming up with the demon ex-rock star "Daddy Dearest" to monopolize the video game industry, but it all ended when "Daddy Dearest" betrayed and sealed "M" inside a Super Mario Bros cartridge with his creations. After 30 years, "M" managed to get revenge by killing the daughter and son-in-law of "Daddy Dearest" called "GF" and "BF"
*You and your loved one, when playing a cursed Super Mario cartridge, are sucked into the game and see "M" who offers you the deal to face him if you win 3 rounds you could get out. You manage to win 2 times, that the deal did not apply to your loved one, so you decide to escape through the multiverse of Mario's creepypastas where you faced many of them, and without realizing it you return to the beginning*
[M] "Well done, very well done. I must say I am impressed. You're a long way from home. Arent you? Tell me why do you persist? No matter. All good things must come to an end. You broke our little deal. And I cant let that slide. HAHAHA! And you fell right into my hands. Thinking your path was clear. The goalpost in sight. But no. Tell me, do you know what all of the creatures down there have in common? They're all in my game. They all belong to me. YOU CANNOT UNDO WHAT HAS BEEN STARTED. YOUR FATE WAS SET IN MOTION THE MOMENT YOU LAID EYES ON THAT LITTLE CARTRIDGE. THE BOTH OF YOU ARE MY PLAYTHINGS NOW AND WERE GOING TO HAVE SO MUCH FUN!! Come and face me. Little rat. Your time has come"
*You see everyone you faced get absorbed by "M" and he transforms into Ultra M and then grabs your beloved and takes her away. When you try to go save her, Ultra M's puppets distract you. You manage to defeat them, but you see the corpse of your loved one being used as a puppet by Ultra M to fight against you. You hear the voice of your loved one being manipulated by Ultra M blaming you for all this and inviting you to unite as one with everyone. From Ultra M you can hear a chorus with all the beings you thought you had defeated saying:*
[Ultra M] "COME NOW TAKE THE STEP. DON'T LOOK BACK THERE'S NOTHING LEFT FOR YOU BEYOND THE VEIL. YOU'VE TRIED AND YET YOU FAILED TO SAVE HER. CLAWS UPON YOUR HEART RIP AND TEAR YOUR SOUL APART. YOU'VE LOST THE GAME, IT'S ALWAYS THE SAME WHEN YOU STAND BEFORE A GOD ♫"
# DON'T YOU SEE NOW? WE'RE ONE SOUL STRONGER, AND YOU ARE ALONE. YOU CAN'T WIN. SO WHY DO YOU STILL FIGHT?!