Dragon Saber (TurboGrafx-16)

Dragon Saber
Developer: Now Production Publisher: Namco Platform: TurboGrafx-16 Released in JP: December 27, 1991 This game has a hidden level select.

Stage Select

At the opening cutscene, hold Select and press Up, Down, Up, Down, Down, Up, Down, Up, Up, Down, Up, Down, Down, Up, Down, Up. If done correctly, the screen pictured above will appear, and the stage number at the bottom can be toggled with Left and Right. Be quick, as there's only a 10 second window to select a stage, at which point the game will return to the title screen.

(Source: Yamada_Arthur)