While the West has been experiencing Elden Ring sales galore ever since the FromSoftware title launched at the start of the year, Japan has a new sales titan on the scene, with that very game being Splatoon 3.
As stated by the Japanese sales information Twitter account, Game Data Library (thanks, GoNintendo), it's said that in just a month since it arrived, Splatoon 3 has sold four million copies in the country alone, both digitally and physically, making it the year's best-selling title in Japan.
As for whether it can retain this record will likely depend on Pokémon Scarlet/Violet and how that fares in the six weeks or so it has before we get to 2023.