Exzisus

Exzisus
Developer: Taito Publishers: Taito (JP), TAD Corporation (US/EU) Platform: Arcade (Custom) Released internationally: August 1987 This game has unused code. This game has hidden developer credits. This game has regional differences. This game has revisional differences.

Exzisus is a side-scrolling shooter with a name that makes it impossible to talk about out in real life. Of course, this assumes that you're talking to people who would bother knowing about obscure arcade games from the late 80s.

To do: The differences between the dedicated cabinet and the conversion release are much more significant than the current section details. Differences include the conversion kit's unique ability to shoot the animal powerups in front of you with button 2, weapons behaving differently, and probably a lot more. Also, better organization of the images.

Developer Credits

At address 0x00050 in CPU-A is this programmer credit:

PROGRAMED BY T.YOSHIKAWA

(Source: タイトーメモリーズ関連 (Taito Memories))

At address 0x07FC4 (also in CPU-A) is a more comprehensive staff list:

STAFF
PROGRAMMER
T.YOSHIKAWA
T.MURATA

(Source: タイトーメモリーズ関連 (Taito Memories))

Over in CPU-B, there's yet another set of credits -- now with pseudonyms! At address 0x00007:

PROGRAMED BY TOM_BOY & MURA © TAITO

(Source: Original TCRF research)

There are two distinct builds of Exzisus: One with its own dedicated hardware, and one that uses the JAMMA board standard.

Anyway, the following set of credits is only on the dedicated version's CPU-B at 0x07FD7:

YOSHIKAWA
MURATA

(Source: Original TCRF research)

Copyright Strings

US	World	US (Under License)
ID: 02	ID: 03	ID: 04

ROM address 0x7FFF in CPU-B controls the copyright strings on the title screen. There are four different strings, meaning that the game (or better, the dedicated version) was planned to get even a release outside Japan, but since this never happened, only the 01 was used. There's an additional copyright ID, 00, which uses the Japanese copyright message without the export warning. The international (of the simple PCB) version published by TAD overwrites the licensed message with "© TAD CORP., 1987" on one line.

Curiously, the Taito Legends release of the game uses the 03 copyright string.

Place this cheat in MAME's exzisus.xml file (or exzisusa.xml for the JAMMA-converted set) to change the copyright information:

  <cheat desc="Copyright ID">
    <parameter>
      <item value="0x01">Japan, Japanese</item>
      <item value="0x00">Japan, English</item>
      <item value="0x02">US</item>
      <item value="0x03">World</item>
      <item value="0x04">US (Under License)</item>
    </parameter>
    <script state="run">
      <action>cpub.mw@7FFF=param</action>
    </script>
  </cheat>

Here's an example of the dedicated version of how appears in the game with the copyright set to World, 03.

(Source: Original TCRF research)

Unused Text

There are two copyright strings in CPU-A that are unused by any means. The first is at 0x7FAD:

©1987 TAITO

The second is at 0x7FB8:

©TAITO CORP.

(Source: Original TCRF research)

Version Differences

Two versions of the game were released: one for a dedicated cabinet, which was only released in Japan, and the other as a simple PCB with less game features, which was released in Japan as well as internationally. In Japan, it was far more common at the time to swap out boards in generic cabinets (colloquially known as "Candy Cabinets"), so these two versions having such considerable differences is a bit of an anomaly.

Disappointingly, Taito Legends only includes the simpler version.

Title Screen and Palettes

Japan (Dedicated)	Japan (Conversion)	International

The palettes in the dedicated version are correctly polished and saturated. In the conversion kit version, the palette are washed out and less saturated. This is because the game now runs in a dark green background rather than a clean black one.

Weapons

Japan (Dedicated)	Japan (Conversion)/International

A barrier upgrade exists in the dedicated version that allows the player to take four hits from enemies without dying. In the conversion kit version, the barrier upgrade was replaced by a destruction power-up which destroys all the enemies on the screen. Also, the text and power-up icons is shifted by one pixel to the right in the dedicated version, making it centered.

This is how appears in-game.

Gameplay

• Firing in the dedicated version uses two buttons: Button 1 for gun and Button 2 for missiles. The conversion kit version maps both actions to Button 1, since Button 2 now is used to shoot the animal powerups in front of you.

Japan (Dedicated)	Japan (Conversion)/International

• The dedicated version has an amazing effect where many enemies emerge from the background and move into the foreground. In the conversion kit version, there's no such effect, as they just simply appear from the edges of the screen.

Enemy Pattern

• Almost all of the enemy patterns in each version are different. The dedicated board's enemy variation is a tad more scarce and enemies frequently appear from the right, while the conversion kit's enemies are a bit more varied in placement and sprite work.

Power-Up

• The conversion kit has a pickup canister that can be shot to obtain powerups. These do not appear in the dedicated version, where shooting a row of enemies will net you an upgrade instead.

Missile Behavior

Meteorita Zone on the dedicated board. Note the various sprites in the background area.

• To coincide with the removal of the background objects in the conversion kit, the missile upgrade no longer fires into the background and instead trails onto the ground horizontally, making it more useful for taking out the laser turrets.

Scoring System and Name Entry

Each version has a different scoring system:

• The dedicated version has a (kind of) unfair scoring system, where after you lost your last life and choose to continue the game, you'll be able to insert your name and keep your current score. This means that if you beat the high score and decide to continue, you'll be always able to insert your name in first place.

• The japanese conversion kit version has a more accurate (and fair) scoring system, where after you lost your last life, you'll be able to insert your name then decide to continue the game or not. If you continue, your score will be reset.

• The international version has a scoring system which is a hybrid between the dedicated and japanese conversion kit version, where after you lost your last life, you can decide to continue the game or not. Continuing you will resume the game at the last checkpoint you reached keeping your current score. The only way to insert your name is to not continue the game.