Thunderbirds (NES)

Thunderbirds
Developer: Pack-In-Video Publishers: Pack-In-Video (JP), Activision (US) Platform: NES Released in JP: November 29, 1989 Released in US: September 1990 This game has unused graphics. This game has debugging material. This game has a hidden sound test. This game has a hidden level select. This game has regional differences.

A mediocre shooter game based on the Thunderbirds license. And no, this was not released in Europe, despite that being the continent of origin.

Unused Graphics

Flashing Eyes

Illuminated eyes for the Tracy brothers' portraits. Presumably the portraits' eyes were meant to flash before cutting to the character's sprite like in the show, but such an animation does not occur in the final game.

Pod 6

An unused pod number for Thunderbird 2's pod sequence. While the cutscene this number is supposed to appear in is unused in the US version, pod 6 is left unseen in both versions of the game since Thunderbird 2 never selects a pod beyond 5.

Debug Menu

At any time during the game, hold Up + Left and press Reset. Then, while the screen is still black, enter A, B, and Select to gain access to a debug menu.

• STAGE - Select the game script to play. Scripts are used for any cutscenes, briefings and other game parts, except the shooter engine. The STAGE 00 is a script number for a Debug Menu itself. The main game starts from 04. The script number 01 is for a CHR data viewer.
• RANK - Choose the difficulty. Unfortunately, there is no difficulty option in-game and the game doesn't increase its difficulty at all.
• DATE - Select how many days the player has remaining. You can select more than 60 days and it can be even written to pass, but some of the higher values cause some problems.
• ENERGY - Amount of ship firepower, used for increasing ship protection from damage. The highest value that can be chosen is 2, so any values above this value will protect you from many more hits, but prevent firing at all.
• MUSIC - Play a music track.
• SOUND - Play a sound effect.

You can't see the cursor in this menu with the US version because of the selected palette for the menu tile maps. You can see it in the Japanese version, although it looks awful because of the different background color for the text strings.

Unused Tile Maps

Among all tile maps, there are at least two noticeable ones, which are unused in both versions of the game. Both have no script assigned nor any code to display it. There are some empty slots for scripts in the script pointer table, which are 02, 03 and 05, which probably were some removed debug menus similar to Debug Menu and CHR viewer, but only tile maps for them are left in ROMs.

Vertical CHR graphics layout (tilemap 05)

The sprite CHR graphics in this game using the vertical storing layout, so it's difficult to see in the CHR viewer with normal tile order. This one was probably intended for a different view mode for the CHR graphics.

Character Viewer (tilemap 07)

Only this tile map remains.

Regional Differences

Title Screen

Japan	US

The copyright information was moved to its own screen in the US version to accommodate the additional copyright and license information.

Stage Select

Japan	US

In the US version, returning to the stage select after completing or failing a stage leaves the cursor on the stage you last attempted or the one closest to it, rather than returning it to the leftmost stage like in the Japanese version. In addition, the US version adds a pink dot to mark completed stages instead of removing them from the map entirely.

Thunderbird 2 Pod Sequence

Unique to the Japanese version is an additional Thunderbird 2 launch sequence depicting it selecting a pod for the following mission, before showing it flying through the sky like in the US version. Interestingly, the tiles for this sequence still exist in the latter despite not appearing in-game.

Staff Roll

Japan	US

The US version scrolls the text a couple rows higher than the Japanese version, possibly to have it better centered. The credits in the JP version also appear letter by letter as it scrolls up.

Sound Differences

Japan	US

The sound effect played when the player is damaged differs between versions, for reasons unknown.