The Ninja Warriors (TurboGrafx-16)

The Ninja Warriors
Developer: Taito Publisher: Taito Platform: TurboGrafx-16 Released in JP: June 30, 1989 This game has a hidden sound test. This game has a hidden level select.

Sound Test

At the title screen, press Select so "Ninja" is displayed as the currently selected player. Press and hold Select to change it to say "Option", then (while still holding Select) press and hold Run to access the sound test.

Level Select

Start the game and allow the player to get killed. As the player explodes, hold Down until the continue screen appears. Repeat the process three more times, holding Left the second time, Right the third, and Up the fourth. The level select should now appear instead of the continue screen.