Babel

Babel
Developer: Laser Soft Publisher: Telenet Japan Platform: TurboGrafx-CD Released in JP: March 27, 1992 This game has unused graphics. This game has debugging material. This game has a hidden sound test.

Not to be confused with The Tower of Babel.

Babel is a dystopian sci-fi RPG starring a pair of heroes tackling the potential destruction of the world and the religious organizations trying to stop and/or engineer it. Much like Xenogears, it was praised for its ambitious story but released in an incredibly unfinished state (one entire chapter of the game is told in non-interactive text). That, alongside being released the day after Tengai Makyou II in Japan, doomed it to obscurity.

Test Mode

At the title screen, press Left, II, II, II, II, Right, Up, I, I, I, I, Down for a test mode allowing you to view story cutscenes and listen to the game's music and voiced dialogue. Selecting OMAKE from the TALK2 menu plays a series of otherwise-inaccessible messages from the game's voice cast.

(Source: Game Tricks Encyclopedia Wiki)

Unused Graphics

Hidden in VRAM while you're outside of the Agamemnon (the ship that serves at the game's final dungeon) is Doraemon waving hello. Given that Minky Momo is visible in the town just before this scene, it's likely that this was going to be another anime cameo Easter egg, but the Agamemnon exterior is only used for one non-controllable cutscene so you're never given a chance to look for it.