"L is Real 2401" is a theory / Easter egg in Super Mario 64. It involves the character Luigi and his absence from the game. This led to a lot of theories and bogus cheat codes about its non-existent aspect.
On July 25, 2020, 24 years and 1 month after the game's initial release in Japan, a leaked beta of Mario 64 appeared on the internet. Among the contents of the beta were Luigi's model and accompanying voice audio.
Super Mario 64 was originally going to be a 2-player game, with Mario and Luigi as playable characters. But the system's capabilities at the time prevented that from happening, and Luigi was taken out of the game. Luigi did, however, finally make his Nintendo 64 debut in Mario Kart 64.
In Super Mario 64's Castle Courtyard, there is a statue in the heart of the courtyard. The statue depicts a giant star with a blurry inscription beneath it. Although it is hard to read, the text on the inscription can be interpreted as either "Eternal Star" or "L is real 2401", depending on the player's viewing angle. While "Eternal Star" made much more sense considering the star directly above the inscription, people quickly latched onto the "L is real" idea. People thought that L stood for Luigi, and therefore Luigi would have been in the game. One theory was that 2401 represented every gold coin in each world of the game and that by collecting them all, the player would have to come back to the statue where Luigi would then emerge as a playable character.
While there were many theories as to what the inscription could mean besides the one above, the most popular and logical theory is that it was a reference to the game Paper Mario. The game was released in America on February 5, 2001 (02/05/01), very close to the date written on the inscription (02/04/01), and Luigi was a character in that game. There is some unintelligible text under the message that might say "In paper M". Although, at that time, Paper Mario was known as "Super Mario RPG 2", which might debunk this theory. This could be a reference to the graphical style of the game as opposed to Super Mario RPG: Legend of the Seven Stars
IGN responded to the number of questions about Luigi by offering a $100 bounty to prove that Luigi was not in the game.
On 25 July 2020, 24 years and 1 month after the release of the game which means 2401 (665-667), the source code was leaked which includes an unedited model of Luigi confirming its existence, thus completing the prophecy.
- The news can also be found above and below Dodongo in The Legend of Zelda: Ocarina of Time.
- The message can also be found in the Dojo Pathway in Club Penguin Rewritten.
- The first Mario title for the Nintendo 64, Super Mario 64, had Luigi nowhere in the game. Mario's first title for the Nintendo GameCube, Luigi's Mansion, didn't show Mario in the flesh until the end of the game and had Luigi as the only playable character.
- Luigi was actually going to appear in a Super Mario 64 sequel, but the game was cancelled due to the commecial failure of the Nintendo 64 DD (Disk Drive).
- On December 2, 2016, on the subreddit, r/retrogaming, the theory was supposedly debunked way before anyone realized in a letter from Nintendo dated May 7, 1998, which is stated that the "L is Real" message is a joke put in there by the programmers. You can read it here: https://www.reddit.com/r/retrogaming/comments/5g6nf0/letter_from_nintendo_about_luigi_in_sm64_1998/?st=j8zfwn9j&sh=fbd2967f
- On July 25, 2020, approximately 24 years and 1 month since the release of Super Mario 64, during a recent Nintendo leak it was revealed that Luigi was planned in the beta of SM64 and even had a model, textures and voice lines prepared.
In 2020, many bits of information about Nintendo's consoles, beta Pokémon data and source codes were leaked. Along those discoveries, there were some n64 and SNES source codes, which includes SM64 data. In that source code, a model, sprites and sound effects of Luigi were present. The SM64 community slowly restored the Luigi model back into the final game. Luigi was discovered after (almost) exactly 24 years and 01 month after the SM64 official release.