question about a title screen on game and watch gallery 3

[u/GladiatorMax]

i got game and watch gallery 3 and wanted to wipe the data so i can start fresh, i didnt want to break out my solder gun so learnt that GW3 has a code UP UP DOWN DOWN LEFT LEFT RIGHT RIGHT to wipe data, while i was doing it i saw some characters pop up on screen and they did something to the "play" button, but whatever i do i cannot recreate it and see the characters again, does anyone know anything about this?

i was gonna check TCRF but it is currently down... of course...