Another world
When "Press Start" appears on the title screen, press R1, Up, L2, Down. If you entered the code correctly a small green wizard will appear in the lower right corner. Start a new game and the phrase "Another World" will appear in the lower left corner. Select a regular puzzle game for 27 slightly faster levels with new backgrounds. Note: If you beat the computer in Player vs. Computer mode, you will be able to select characters next time around.

Character select
Start a puzzle game. Then, at the map (alphabet) screen, press Left(2), Up, Down, L1 + L2 + R1 + R2. Now a character select screen will appear. Press Left or Right to select a character and press X to continue. Note: Bub will appear on the map screen, but your new character will be in the game.

Extra credits
In the option menu, press Left, Right, R1, R2, L2, L1, Up, Down. A 30-second timer will appear in the upper-right corner. Quickly highlight the "Credit" selection and repeatedly tap X or Circle to add up to 30 credits!