This is a au where MX’s game is called “Mario And Luigi: Playground Adventure” (the (in-universe) game is also the au’s name). And he convinced all the players that he is actually Mario and Lucas is Luigi. When a player enters a secret room, he/she can see that “Mario” (MX) torturing “Luigi” (Lucas). After that, the room will never be found ever again.

(the lore is still wip)