Title Screen
US Version Japanese Version
Beyond the obvious difference in language, the Japanese title was also changed from "Godzilla: Domination" to "Godzilla: Great Monster Fray Advance", which was the same title as the Gamecube's Godzilla: Destroy All Monsters Melee in Japan, sans "Advance". The overall title design is also much more ornate and eye catching compared to the US one.

Character: Godzilla
By the time the title was being prepared for its Japanese release, production on Godzilla: Tokyo S.O.S. (2003) was in full swing. Interested in capitalizing on the latest movie's impending release, Atari altered the game slightly with a few references from that movie that were implemented on the character roster. For Godzilla, the designers changed his skin color from the stereotypical green to a gray tone, more reflective of the bulk of his movie appearances. The other change, one that clearly ties in with the 2003 film, was the addition of a scar marking on the King of the Monster's chest, which was caused by Kiryu in the previous movie: Godzilla Against Mechagodzilla (2002). This change is less noticeable on the creature for his "in game" appearance, but is very recognizable on the larger "match up" view. Move wise, though, Godzilla is entirely unchanged.
Character: Mechagodzilla
The most drastic change to the characters is Mechagodzilla, who takes on the visage of Kiryu from Godzilla: Tokyo S.O.S. (2003) as opposed to the Heisei series version. These changes include: alterations to the character's dorsal fins, the addition of the rocket launcher pack to his shoulders, a drill hand and more. Regretably, though, the character has the same exact moves as the Mechagodzilla in the US version; in fact, even the look of the moves is retained, which is particularly disheartening for the character's missile attack as the "boxed" rocket launchers still emerge from his back to unleash missiles, rather than using the ones already located on Kiryu's shoulders. For reference, the character's drill hand goes entirely unused in this game. It should also be mentioned that the ending for Mechagodzilla still showcases the Heisei version as well.
Character: Mothra

The last of the altered characters, Mothra also features the least noticeable changes over its previous incarnation. In fact, in game, there are only two noticeable differences compared to the US version. The first is that the white coloring of the character has been dropped and replaced with a very light and "earthy" brown. Secondly, the mouth was altered from the "two prong" look to one that more resembles the brown one seen in the films. Despite their efforts, though, the character still looks most reminiscent to her appearance in Godzilla, Mothra and King Ghidorah: Giant Monsters All-Out Attack (2001) as opposed to any other film. The "match up" look to the character has been changed around more noticeably, though, as its eyes were changed to a teal hue, while the mouth was completely redone and the overall coloring was changed to more reflect its appearance in Godzilla: Tokyo S.O.S. (2003); however, its wing coloring is still distinctly that of the 2001 version.

  It should be noted, that Mothra actually has one of its moves changed for the Japanese version. The move in question is the character's poison powder, which instead of being colored the previously questionable vibrant purple is now a very light brown; an alteration that looks more in line with its use in Mothra vs. Godzilla (1964). The change, though, is only cosmetic, as the attack itself has the same effect.

Player Notation
A very small change, but a symbol, such as "1P" or "2P", now appears above all human controlled characters outside of Story Mode in the Japanese version.
Story Options
Arguably the neatest feature of the Japanese version is the additional options for Story mode. In total, there are three modes of play: "default", "survival" (no continues, life does not refill between matches), "rage" (all players start the match with a full meter that continues to grow by the second). The "rage" option changes the game up a lot, as new things are possible such as firing Kiryu's missiles three times in a row. However, it also shifts the balance between the characters dramitcally; for example, Rodan can finish off most opponents in a matter of seconds with his Beak Charge.
Stage Order
In the Japanese version, the stage order has been juggled around quite a bit. The second stage is now a one-on-one match (instead of two-on-one); stage three is now two-on-two (instead of one-on-one); stage four is a three monster free-for-all (instead of a two-on-two); stage five is a four monster free-for-all (instead of one-on-three); stage six is a one-on-three match (instead of one-on-one); stage seven is a one-on-two match (instead of a four monster free-for-all). Both the opponents and allies of these stages are now completely random as well.
Bonus Stages
For the Japanese version of the game, the bonus stages have been removed, greatly speeding up the time it takes to reach Mecha-King Ghidorah.
US Version  
No one is probably surprised by the fact that the in game language appears as Japanese in the version released in Japan. What is worth noting, though, is that this is the only language available in that version, compared to the US one which supported: English, French, Dutch, Italian and Spanish.
Company Credit
By the time the game was released in Japan, Infogrames had made a transition from their previous title to that of Atari, an asset which they acquired as part of a deal in 2001. By May of 2003, the company made a full switch to utilizing the Atari brand name, dumping the title of Infogrames which they had previously operated under. The Japanese version of this game, which was released in 2003, reflects this change.
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