All cheats for this game by platform:
GameBoy
Downloadable Pri Pri Cheats
Primary Collection of Cheats
Level select
Press [Up]x2, [Down]x2, [Left], [Right],
[Left], [A], [B]x3, [A] at the main menu.
A sound will confirm correct code entry.
Faster game
Press [A]x3, [B]x3, [A], [B],
[A], [Start] at the title screen.