In the files for Star Fox 64 found in the 2020 Nintendo Gigaleak are references and assets for what appears to be a scrapped level named "Battleship". The string fox_map.c interchangeably calls it "Battleship", "Giant Battleship", and "Ground Ship"; it's possible that the latter could be a mistranslation of "Grand Ship", as they're spelled the same way in Japanese. The stage used a full 3D model, like Area 6 and Bolse, as its icon on the map selection screen. Its intended location was where Sector Y currently sits on the Lylat map selection screen, which is the hard path taken from Corneria, and its two branching pathways were known to be Zoness on the hard route and "Fortuna" (Fichina) on the normal route. According to the string fox_play.h, it was an all-range mode stage, and the audio_game.h string makes it appear that it was going to reuse Bolse's theme for its background music, implying that there would have been multiple phases for the level. This stage also had its own enemy data file, implying that it would have featured other enemy ships of some sort.

In October 2024, a group of modders and hackers responsible for the Star Fox 64 Decompilation Project were able to recreate this discarded stage via a fanmade patch.

Hidden in the files for Star Fox 64 are what seem to be remnants of an unused first-person turret mode. Several files reference a stage with the initials "SB", with its header file, fox_sb_poly.h, being titled "スター ブレード 擬き" (Sutā burēdo ki). This translates to "Star Blade Imitation", named after the 1991 on-rails space shooter by Namco, where the ship's guns can only be used in first-person. Dylan Cuthbert and other developers of the original Star Fox admitted to being heavily inspired by Star Blade, claiming that one of their main goals was to recreate the experience of the game.

The file, fox_play.h, defines 3 scroll types of levels: corridor, all-range mode, and "JYUZA", or "銃座モード" (Jūza mōdo), which translates to "Gun turret mode". This file also defines five player modes: ARWING, TANK, SUB, HUMAN, and P_JYUZA, While the SB stage is listed with the other corridor stages, it still specifies that it's in the "JYUZA" category. The SB stage itself appears to be a shortened copy of the Area 6 stage devoid of any content except for one Moras enemy, suggesting that it and other stages were meant to be played in the turret mode during development.

In the game's source code, stages such as "SB", "CL" or "Colony", and Area 6 are subtitled "Great Fox", suggesting that the Great Fox mothership was also intended to use the turret mode. It would likely have been about firing lasers and guns from the ship while trying not to take damage, as there is a string for the ship's health bar named gfox_life. The game's levels, such as the Landmaster stages, are organized into overlay groups to save on memory; Area 6 strangely isn't grouped within the turret mode stages, but Sector Y is.

This unused game mode was restored via a fanmade patch on October 30, 2024, taking a few liberties to make up for the missing code and assets.

Some lines in the opening prologue stage for Star Fox: Assault contain allusions towards dialogue from Area 6, one of Star Fox 64's final stages. In the latter, Caiman says near the end that "The last line has been breached!", and the Area 6 commander will respond with "These guys are crazy!". In the Japanese version of Star Fox 64, the latter instead says "こいつら、化け物か！" (These guys are monsters!)

In Star Fox: Assault's prologue, one of the ape soldiers apart of Oikonny's rebellion will similarly shout that "Our final line of defense has been penetrated!". Oikonny in response says "Is this guy some kind of demon?". In the Japanese version of Assault, he instead says "コイツら化け物か？" (Are these monsters?), which makes it much more clear that it's meant to be a callback to Area 6's dialogue. This intention was confirmed by producer Takaya Imamura in a 2005 Nintendo Dream interview with Star Fox: Assault's development team.

According to former Nintendo character designer Takaya Imamura, Wolf O'Donnell was inspired by his grandfather, who he described as being a "bad man".

In Star Fox 64's ancillary material, Planet Aquas is said to be an entirely water planet with its surface 100% covered by oceans. Star Fox Command however, would contradict this by showing there to be islands on Aquas in the Slippy's Resolve ending; Command's official Japanese guidebook even claims that Aquas' surface is now only 80% comprised of oceans.

In a Q&A with Takaya Imamura in 2023 on this subject, he theorized that perhaps, somewhere in-between the events of Star Fox 64 and Star Fox Command, the islands were created by underwater volcanic belts within Aquas' oceans, likening it to the emergence of Nishinoshima, a volcanic island in the Ogasawara Archipelago.

According to Takaya Imamura in a Q&A in 2024, James McCloud, Fox's father, seemingly returning from the dead to help Fox escape from the depths of Venom at the end of Star Fox 64's hard route was inspired by Obi-Wan Kenobi returning as a ghostly mentor for Luke Skywalker by the end of the 1977 film "Star Wars: Episode IV - A New Hope".

According to Imamura, whether James is actually still alive, or some kind of ghost or vision that Fox saw, is ultimately up to the players to decide. Curiously, while Star Fox Zero (whose story is mostly just a straightforward retelling of Star Fox 64) also contains a sequence at the end where an apparition of James guides Fox through Venom, it appears that Andross can also see him, even shouting:


Which further adds to the ambiguity on whether James is still alive or not.

Beta Star Fox 64 footage circa 1996 shows that Corneria was originally covered in snow. Early footage of the boss fight with the Granga robot even showed it capable of blowing snow as an attack, possibly indicating that it was responsible for Corneria's current state in this build.

Originally, the development team behind Star Fox 64 themselves actually tried to provide the voice lines for the characters:


As mentioned by Takaya Imamura above, this was met with negative reception internally and thus they switched over to using professional voice actors. What remains of this lost developer dub was recently discovered within the Nintendo gigaleak from 2020.

The official Japanese Star Fox 64 guidebook reveals that it was programmer Nobuhiro Sumiyoshi who provided the original voice for Leon Powalski, who is voiced by Shinobu Satouchi (who also voices Fox McCloud) in the final Japanese version of Star Fox 64. Takaya Imamura later revealed in a tweet in 2024 that he provided the initial voice for Fox.

Planet Zoness was originally a beautiful water planet similar to its twin planet, Aquas. It was famous for its resorts and was where Peppy Hare had taken his wife, Vivian, for their honeymoon. However, Andross' forces would invade and pollute its waters with their bioweapons, mutating the local wildlife to become larger and violent.

Early footage of Star Fox 64 circa 1996 actually show Zoness in its pure, unpolluted state, which seems to indicate that making it polluted was decided on later in development. There's actually appears to be dialogue remnants of this cleaner version in the developer's dub:


When finishing the stage:


But in the final polluted version, this exchange in the JP version goes:

The go-to term for the initial conflict of the Star Fox series, as told in three different installments (Star Fox on SNES, Star Fox 64, and Star Fox Zero), is the "Lylat Wars". This name originates from the original PAL release of Star Fox 64, where it was renamed to Lylat Wars due to trademark issues (similarly to why the first Star Fox was renamed to "Starwing" there as well). In comparison, its 3DS remake, Star Fox 64 3D, would retain the Star Fox 64 moniker in all regions. Nintendo would later actually canonize the "Lylat Wars" moniker as the official name of the conflict against Andross' forces in the opening prologue to Star Fox Zero.

In a June 1997 Nintendo Dream interview with Shigeru Miyamoto regarding Star Fox 64, when asked if he would produce a sequel, Miyamoto responded with:


Funny enough, both of these ideas would come to fruition with future titles such as Star Fox: Assault, which hugely emphasized its multiplayer battle mode, and Star Fox Command, which revisited many of the real-time strategy elements that were previously experimented with in the then-unreleased Star Fox 2.

An earlier logo for Star Fox 64 found within the 2020 Nintendo Gigaleak seems to indicate that its subtitle was, at one point, going to be "The Cosmic Crisis".

Star Fox 64's development didn't actually begin with the intention of creating a new Star Fox game; rather, it began with a series of experiments by character designer Takaya Imamura and programmer Kazuaki Morita. As Morita was new to 3D programming, creating something entirely new was difficult, and to make matters worse, they didn't have the final N64 hardware itself to work with, instead having to utilize a bulky dev computer and a modified SNES controller without analog sticks, as those were all being used by the Super Mario 64 development team, which were clearly given far more priority. The pair decided to begin development by porting the original Star Fox, which they thought would be better for easing into 3D. As this was Morita's first attempt at learning 3D, he began with inputting his own data and placing objects like cubes on a course, and then launched basic-looking Arwings. This prototype was affectionately named "Star Box".

It's worth pointing out that Star Fox 64's development wasn't given the full greenlit until the project was displayed at Space World 1995, as the higher ups within Nintendo were not actually keen on the concept and were even waiting for Imamura and Morita to eventually give up on their experiments. It was because of their dedication and perseverance to get the game off the ground that led to Star Fox 64 beginning full production as an actual video game after it was shown off at Space World, with Shigeru Miyamoto and other Nintendo staff such as director Takao Shimizu slowly coming on board afterwards.

One of Falco Lombardi's most famous lines in Star Fox 64 is "Hey, Einstein! I'm on your side!"

This line is somewhat controversial because it implies that there exists some version of scientist Albert Einstein within the Star Fox universe. It is worth pointing out that this was added in for the Western localization of Star Fox 64, as in the Japanese version of the game, Falco simply just says:


Ultimately, the Western version of Star Fox 64 3D would have this line be changed to: "Hey, genius! I'm on your side!"

Star Fox 64's infamous Killer Bee enemies were actually designed and implemented by Shigeru Miyamoto himself. Miyamoto wanted to include them throughout development and after insisting upon it, he was told by the development team to design the enemy himself. He then drew up three different designs and asked which one the team would utilize in-game, with the final design being used near the end of development.

Many Star Fox 64 players have referred to the Venom army general piloting the mecha boss encountered in the Easy Route Corneria path as "Granga", presumably because of the Star Fox 64 Nintendo Power Official Strategy Guide referring to him as such.

In reality, or at least going by the official Japanese Star Fox 64 guidebook and also Star Fox 64 3D, the name "Granga" actually refers to the aforementioned mecha itself. Like most of Andross' lieutenants (with the exception of Caiman), the pilot himself seemingly never had a proper name.

As admitted by Mitsuhiro Takano (the original script writer for Star Fox 64) in an issue of Iwata Asks regarding Star Fox 64 3D, the development team had initially planned on including more aquatic stages based around the Blue Marine in the original game, but these were removed because they felt they dragged down the pace too much. In the Japanese version of the Aquas stage in Star Fox 64, Falco says:


English SF64's equivalent to this is "This thing will never hold together."

Apparently, this was the result of Takano feeling bad about there only being one underwater stage in all of SF64's single-player mode.

In Star Fox: Assault's campaign, it is revealed by Beltino Toad, Slippy's father, that the Aparoids had already attacked the Lylat System 17 years prior, where an entire Cornerian fleet was destroyed by a single Aparoid, the same type that destroyed Oikonny's flagship and attacked the Star Fox team on Fortuna.

In a 2011 Nintendo Dream magazine interview with Takaya Imamura, he explained that rather than having the Aparoids suddenly appear, he felt that it would be better have something that was already there in the past so there would be a connection and give the story more depth. This is also why it was decided to have Beltino, who was previously stated to have worked for Space Dynamics in ancillary material for Star Fox 64, to be in charge of the Cornerian army by the time of the events of Star Fox: Assault.

Imamura explains that, with Beltino being a genius scientist, he was doing various military commissions and Space Dynamics work in the form of a commissioned employee over the years, explaining how he fought against the Aparoids as apart of the Cornerian Army 17 years priors, later joined up with Space Dynamics by the time of Star Fox 64, and then eventually returned to the Cornerian Army by the time of Star Fox: Assault.

Despite the English version of Melee using Star Fox Adventures' voice cast in the game's Corneria and Venom stages, the Japanese version uses all of the original Star Fox 64 voice actors. Shinobu Satouchi, Hisao Egawa, Kyoko Tongu and Tomohisa Aso all reprise their roles as Fox, Falco, Slippy and Peppy respectively. The former two's voice clips are also used for Fox and Falco as fighters even abroad.

Contrary to the Western version of the game, which more or less started over with a completely new and different cast, Star Fox: Assault's Japanese voice cast would actually bring back quite a few of the voice actors from Star Fox 64's Japanese dub:

• Hisao Egawa (Falco)
• Kyoko Tongu (Slippy)
• Tomohisa Aso (Peppy)
• Daisuke Gori (Pigma)
• Shinobu Satouchi (Leon)

Of the returning cast from Star Fox 64, the only characters to be recast were:

• Fox (voiced by Shinobu Satouchi in SF64, now voiced by Kenji Nojima)
• General Pepper (voiced by Daisuke Gori in SF64, now voiced by Michihiro Ikemizu)
• Wolf (voiced by Hisao Egawa in SF64, now voiced by Mahito Ōba)
• ROB 64 and Andrew (both were voiced by Daisuke Sakaguchi in SF64, now they're both voiced by Yusuke Numata)

According to Takaya Imamura in a Nintendo Dream interview regarding Star Fox Assault, Fox's new voice was meant to represent a middle ground between Steve Malpass' nasal sounding voice from Star Fox Adventures and Shinobu Satouchi's voice from Star Fox 64. Apparently, Satouchi was saddened when he discovered that he'd be returning to only reprise his role as Leon in Star Fox: Assault.