Display game time in Galaga Arrangement
At the Galaga Arrangement title screen, press Left, Right, Left, Right, Up, Down, Up, Down.

Pac-Attack mode
Get a score higher than 25,000 points in Pac-Man to unlock Pac-Attack mode.

Pac-Mania mode
Get a score higher than 20,000 points in Ms. Pac-Man to unlock Pac-Mania mode.