Easter Eggs Wiki
Game N64-133-2 31767

Super Mario 64 is a game that follows the adventures of Mario saving Princess Toadstool (yet again!) by collecting stars, which Bowser scattered throughout the castle, most of them being inside of paintings.

L is Real 2401/ Eternal Star[]


When you go to the backyard of the castle, you should see a fountain with a star sculpted atop. Underneath the star is a plaque that says either "Eternal Star" or "L is Real 2401". That last one raised many theories that Luigi, Mario's Brother, is an unlock-able character in the game. However, many skeptics proved otherwise.