Puyo Puyo~n Party is a Japanese exclusive N64 game that made use of the Transfer Pak when connected to Puyo Puyo Sun, another Japan exclusive title.
When connected, the images unlocked in the Gameboy game become viewable on the TV through the N64 game. However, there are pictures hidden within the game’s data that are only accessible through clever means. See them all here. The GB game doesn’t explain the criteria to unlock these images; you just need to play it and hope for the best.
