Old School

On the main menu, type UP UP DOWN DOWN LEFT RIGHT LEFT RIGHT B A.
How to find it, step by step
- On the main menu, type the old cheat code with the keyboard: Up, Up, Down, Down, Left, Right, Left, Right, B, A.
- The logo turns rainbow for a moment. It counts.
Reward
A rainbow logo.
In-game hint
An old cheat code still works here.