Won't spoil it, but Up Up Down Down Left Right Left Right B A Select Start on the main menu.
Konami Code Secretssss
- Thread starter AbsolPowers
- Start date
It's apparently some real big end game spoilers for what you unlock with the code, and you unlock the material when you beat the game anyways so it's pretty useless if you don't like getting spoiled. It is cool they implemented it though.