Hidden sticker packs are found under, near, or around green banana bunches. To obtain these hidden treasures, find a green banana bunch, and use Donkey Kong to slam the ground (hold Down and press B). You should see a tiny rectangle bouncing on the ground. Collect it and then turn off the game. Turn the game back on, select the "Print" option at the main menu, then go to "Sticker Book". You should find a small picture on one of the pages. Press A on one to print it. Note: This requires a Game Boy Printer connected to the Game Boy Color via a link cable.
Note: You must have a 2.1 or higher version of the Game Shark to use these codes in a Game Boy Color system.