
The game's data contains unused sprites for Rubber Soul detransforming into his true form while lying down on the floor. This is likely an special knockout animation that would play after Rubber Soul is defeated under certain conditions.
In a video interview with former Capcom game designer Shinichiro Obata, he stated that the reason why the character Pet Shop is so overpowered to the point of being banned in competitive play is because he was originally intended for the PlayStation version and not arcade one, as such he wasn't really intended for competitive play.
However when the updated arcade version JoJo's Bizarre Adventure: Heritage for the Future was in development, Pet Shop was added as a playable character and Mr. Obata couldn't help but notice how weak this version of the character was. So he started doing everything he could to buff Pet Shop, with Mr. Obata himself remarking that he “might’ve overdone it”.
However when the updated arcade version JoJo's Bizarre Adventure: Heritage for the Future was in development, Pet Shop was added as a playable character and Mr. Obata couldn't help but notice how weak this version of the character was. So he started doing everything he could to buff Pet Shop, with Mr. Obata himself remarking that he “might’ve overdone it”.
JoJo's Bizarre Adventure: Heritage for the Future was named after Stardust Crusaders' (the story arc in which this game is based on) original name during serialization in Weekly Shōnen Jump, Part 3 Jotaro Kujo: Heritage for the Future.
In the 34th entry of the Anime News Network series Jason Thompson's House of 1000 Manga, Jason Thompson stated that Capcom USA was disatisfied with how Jojo's Venture was doing in arcades at the time, to the point that he was told by a Capcom USA employee that they wouldn't release the game on home consoles "unless CAPCOM Japan forced them to".

An image used during the E3 presentations can be found within the Dreamcast version's game files "DASH" and "JOJO" folders under the name "E3TITLE.PVR"

The Japanese onomatopeia used for the character select screen of JoJo's Venture was removed in the international release.
While the English release features a generic "Here comes a new challenger!" message, the original Japanese version features three different ones depending if the selected character is either a hero, female or villain.
If the player is using a hero character the text will say "A new stand user, huh!", whereas the text used for both females and villains are variants of the same phrase: "Who are you!?"
If the player is using a hero character the text will say "A new stand user, huh!", whereas the text used for both females and villains are variants of the same phrase: "Who are you!?"
All Japanese voice lines were removed in the Asian (Non-Japanese) versions of the game, leaving behind only the grunts and English words.
If the player is using Hol Horse (w/Boingo) and starts shooting Up and Down, a glitch will occur where a multi-hit, floating Boingo trap will appear. The Boingo trap stays in the air until the opponent touches it, and deals 10 hits in total.
Oddly enough, the American back cover of the Dreamcast version mentions the Super Story mode when that mode was exclusive for the PlayStation port.
The game pays homage to other JoJo-related media that came before it; in this case, the OVA:
• One of Avdol's alternate color schemes turns his coat red and shirt to yellow, similar his appearance from the 1993's and 2001's OVA. The same goes for Joseph Joestar, Polnareff, and Black Polnareff, all of them having alternate color schemes that resemble their OVA apparance.
• One of Iggy's special moves make him create a giant wave of sand in his opponent's direction, similar to how he attacked Vanilla Ice in the OVA.
• One of Avdol's alternate color schemes turns his coat red and shirt to yellow, similar his appearance from the 1993's and 2001's OVA. The same goes for Joseph Joestar, Polnareff, and Black Polnareff, all of them having alternate color schemes that resemble their OVA apparance.
• One of Iggy's special moves make him create a giant wave of sand in his opponent's direction, similar to how he attacked Vanilla Ice in the OVA.

According to early concept art, more characters from part 2 of the JoJo manga series were planned to be playable, including Stroheim, Kars, Esidisi, Wamuu, and Wired Beck.
Besides being based on Part 3 (Stardust Crusaders), this is the first game to have elements from more than one JoJo saga:
• Part 1: Wang Chan as Shadow Dio's "child" form during Alessi's stand ability, a shot of the Stone Mask appears when a character is stand crashed, and both versions of Dio have Space Ripper Stingy Eyes as a special move.
• Part 2: Young Joseph is a playable character, Caesar appears in the Young Joseph's special move that contains several manga panel flashbacks as well as Lisa Lisa doing the same for Old Joseph's version, the Red Stone of Aja is used as one of Young Joseph's supers and the crossbow he used against Wamuu, as well as the coke bottle during his introduction scene, appears in his moveset.
• Part 4: The arrow appears during Polnareff "Requiem" super, one of Jotaro's alternate color scheme recolours his coat, hat and pants white, much like his Part 4 outfit and in one of Dio's alternate color scheme, The World is pink and blue giving it an appearance similar to Crazy Diamond.
• Part 5: Silver Chariot Requiem appears as a super combo for Polnareff and one of his win quotes translates to "We'll meet again in the future...in Italy".
• Part 1: Wang Chan as Shadow Dio's "child" form during Alessi's stand ability, a shot of the Stone Mask appears when a character is stand crashed, and both versions of Dio have Space Ripper Stingy Eyes as a special move.
• Part 2: Young Joseph is a playable character, Caesar appears in the Young Joseph's special move that contains several manga panel flashbacks as well as Lisa Lisa doing the same for Old Joseph's version, the Red Stone of Aja is used as one of Young Joseph's supers and the crossbow he used against Wamuu, as well as the coke bottle during his introduction scene, appears in his moveset.
• Part 4: The arrow appears during Polnareff "Requiem" super, one of Jotaro's alternate color scheme recolours his coat, hat and pants white, much like his Part 4 outfit and in one of Dio's alternate color scheme, The World is pink and blue giving it an appearance similar to Crazy Diamond.
• Part 5: Silver Chariot Requiem appears as a super combo for Polnareff and one of his win quotes translates to "We'll meet again in the future...in Italy".
Performing a time stop with the characters Dio or Jotaro after an opponent has been defeated sometimes causes a glitch where the opponent remains frozen for several seconds into the next round. This virtually guarantees another loss for them, as even a single hit while frozen like this causes a large amount of damage.

Iggy's second special seems to be a reference to Akuma's famous Shungokusatsu from the Street Fighter franchise, also developed by Capcom. Aside from the similar animation, the game's data contains an unused sprite of the kanji for dog (犬,inu), parodying the kanji for heaven (天,ten) that appears during Akuma's Shungokusatsu.

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After beating arcade mode, a short cutscene plays of the selected character finishing DIO. In the US version DIO flies offscreen, while in the uncensored version of the game DIO instead splits apart and violently explodes, much like his death in the manga.
The N'doul bonus stage has a dead Speedwagon Foundation helicopter pilot in the background. The character was removed from the US version of the game because not long after the start the stage, one of N'Doul's Geb water hands attacks the pilot's beeping wristwatch and cuts his hand off.

Creator Hirohiko Araki is known for having a strong preference for western music, because of this most characters reference a popular band or song in some way. This meant it was necessary to rename some characters to be acceptable for release outside Japan. Examples of name changes include Devo to D'bo and Vanilla ice to Iced, although some references are still included, such as Iced quoting Ice Ice Baby with "You had a problem.... I just solved it." in JoJo's Bizarre Adventure: Heritage for the Future.
N'Doul (or N'Dool in the localized version of the game) was originally planned as a playable character, artwork exist that show how he would have fought, along with an Alessi form. It's possible to hack the game to choose N'Doul as a character, showing that a number of assets still exist in the games files, such as an alternate colour, animated life bar portraits, animated super move and VS screen portraits and a cut-in for the "Here Comes A New Challenger!" screen.

The games data contains sprites for Joseph using his Hermit Purple as a grappling hook, which was likely intended for a mid-story cutscene, Spoiler:when DIO is chasing Joseph around Cairo, which would closer match the anime and manga.

In the international version, Chaka's blade is coloured brown while in the Japanese release, it is silver. However, Khan and Black Polnareff's swords remain unchanged in both versions,Spoiler:despite the fact that all the 3 characters are technically using the same sword in the storyline.
Sho Hayami, the voice actor for Vanilla Ice in the original game, later reprised his role in the animated adaptation of JoJo's Bizarre Adventure: Stardust Crusaders, over 15 years later.

In the 1993 JoJo RPG for the SNES, Midler was portrayed as a stewardess, making it the first time she had a physical appearance. Seven years later, when Capcom was producing JoJo's Bizarre Adventure, they wanted to include Midler as a playable fighter in the game. However, as she was only shown from the waist-down in the manga, and the game was a more faithful adaptation of the source material, they asked Hirohiko Araki to redesign her into something like a belly-dancer with her face covered up. Since then, as shown in the JOJO A-GO!GO! artbook, this new look is now her default appearance.

Unused sprites for Tower of Gray/Gray Fly can be accessed via the game's debug menu. Information for assembling the sprite is unfinished, and thus uses Jotaro's sprite assembly method instead. The sprites for Gray Fly are mostly finished, which includes various attacks and death animations.
These sprites would later be used in the PSX port, where Gray Fly is an enemy in Super Story Mode.
These sprites would later be used in the PSX port, where Gray Fly is an enemy in Super Story Mode.