Mario: Mafia Years is a game released in 1970 by Neenteendo. It involves Mario when he was in the Toad Mafia killing innocents.
The whole thing is an open world adventure set in the Mushroom Kingdom. The world is so huge it will take 1112 lifetimes to traverse half of it, and there is precisely one building which you cannot enter. Due to this fact, the innocent civilians are extremely difficult to locate and you spend the whole game walking in blank nothingness.
As a child, Mario decided to join the Toad Mafia under Todd the Toad. He has to murder one innocent nameless toad.
People call the game “Amazing even though it’s just walking in emptiness. IGN gave it a 5642/10.