The Flintstones: The Rescue of Dino and Hoppy

The Flintstones is an NES game by Taito, which has a dummied-out debug menu.

US version
The game stores a sequence of button presses in memory at the title screen, but jumps right over the code that checks them! To reactivate the routine, enter the following Game Genie codes: (to jump straight to the debug menu, replace the first code with ).

After the codes are entered, wait for the "PUSH START BUTTON!" text to appear, then press Up, Right, Right, Right, Down, Down, Down, Down, Left, Left, Start. If you mess up while entering the code, you can press B to start over.

You'll then be presented with two options, NORMAL or NOHIT. NORMAL is just what it says: gameplay will be unaltered. NOHIT, on the other hand, enables some interesting features. Fred will pass through enemies unharmed, and will start with all three special abilities (FLY, JUMP, and DIVE). FLY and DIVE can be used for free, provided you have enough coins to cover the usual cost. Pressing B on controller 2 will freeze or unfreeze the game; while frozen, A will advance the game frame-by-frame (or you can hold it for slow-motion).

After selecting one of the two options, a number will appear. This number acts as both a sound test and scene select. Press Up or Down to change the number, A to play the selected music or sound effect, B to stop it, and Start to start the game at the selected scene.

Japanese version
The Japanese version of the game has the cheat sequence enabled and working! Wait for the "PUSH START BUTTON!" text to appear, then press A, A, B, B, Right, Down, Down, Down, Down, Down, Down, Down, Left, Start. Everything else works the same as the US version.

Test mode
In addition, the Japanese version has a "Test Mode", which skips the "NORMAL/NOHIT" portion and just goes to the stage select/sound test. To access it, wait for the "PUSH START BUTTON!" text to appear, then press A, B, A, B, Up, Right, Right, Right, Down, Down, Down, Down, Left, Left, Start.

Unused title screen animation


Apparently, the little Fred at the top of the title screen was supposed to be animated. No code has been found to display the extra frames, though.

Unused Enemy


The game contains a fully-coded and functional enemy that is never used anywhere. It is a variation of the enemies in the final stage that bounce around on springs. The difference is that this one hovers in the air in a swooping motion and fires a gun in three possible directions.

Unused Graphics
The Flintstones ROM contains a plethora of unused graphics. None of them appear to have any behavior patterns coded in for them.

The Flintstones game was released later in Japan than it was in America and some of these graphics were cleaned out of the Japanese version's ROM, including the dragon, fan blades and bolts, tilted logs, and the snail shell.