Solar Crusade (CD-i)
This game has hidden development-related text.
Solar Crusade is the sequel to Chaos Control. It was intended for release in 1996, but for whatever reason ended up not coming out until 1999, making it the last official CD-i game.
Located at 0x51F9FC, near a list of the game's cutscenes and levels, is some text relating to several debugging features:
[MEM] Memory Map [ N ] Sound report [ N ] Enable Pcl status display [ N ] Hard Debugger exit [ N ] Disable FMV error handling [ N ] Disable soundmaps [ N ] Enable error messages [ N ] Invincibility
Whether they can still be accessed in-game is unknown.
Much like its prequel, a build date and some version info can be found at 0x51FB89:
Solar Crusade V1.0 UK May 22 1996