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.

An early working title for Star Fox Command was merely "Star Fox DS".

Each playable pilot in Star Fox Command has their own unique character musical themes suited for them. Of the playable cast, Fox, Falco and Slippy are unique in that they're the only characters to have additional themes when attacking enemy bases. Fox's enemy base theme in particular is a rearrangement of the Area 6 theme from Star Fox 64.

According to the official Japanese guidebooks for both Star Fox 64 and Star Fox Command, Meteo (or "Asteroid Belt" as it's referred to in Command) is said to represent remnants of a destroyed fifth planet from the early days of the Lylat System, which aligns with its close proximity to Corneria, the fourth planet of the Lylat System. It is said that many of the asteroids there contain highly pure metals, and their outer edges have been the site of high-quality mineral deposits, though ultimately what lies in the deepest parts of the asteroids remains unknown.

This information would also appear on the official western Star Fox 64 website and also in the Star Fox 64 Official Player's Guide, though strangely enough, the latter states that Meteo is believed to be the remnants of a ninth planet from the early days of Lylat.

Two of the game's endings make references to the F-Zero series. In the first ending, "Goodbye Fox", Falco Lombardi can be seen wearing a pair of boots that belong to F-Zero's Captain Falcon. In another ending, Fox and Falco are seen entering the "G-Zero Grand Prix", a mock up of the F-Zero Grand Prix. What's more, the two convert their fighter ships into racing vehicles, as did a character in the F-Zero games known as James McCloud, himself a tribute to James McCloud of the Star Fox games.

One of Star Fox Command's most infamous endings see Krystal ousted from the Lylat System and becoming a bounty hunter named "Kursed" in another galaxy. Looking at the Japanese script however, reveals a slightly different story:


A direct translation of this into English would be:


It shows that Krystal instead renames herself to クラゾア (Kurazoa), which translates to Krazoa.

This is clearly a reference to the ancient tribe that once ruled Dinosaur Planet in Star Fox Adventures, similar to how her spacecraft is shaped and named after the CloudRunner tribe from that game.

According to Takaya Imamura in a 2011 Nintendo Dream magazine interview, frogs in the Lylat System are born as tadpoles and remain as such until they're a month old. He even explains that Slippy and Amanda's baby seen in the "Slippy's Resolve" ending in Star Fox Command was one month old already, hence why it appears as a frog. Imamura would later illustrate this fact in comic form to commemorate the release of Star Fox Zero.

On the Japanese website for Star Fox 64, Slippy mentions certain background characters who would appear in future installments:

• Peppy's wife, Vivian Hare. According to Slippy, Peppy took her to planet Zoness for their honeymoon, which explains why Peppy is so distraught at its polluted status in SF64. Vivian would appear in-game for the first time in Star Fox Command, where it's revealed that she and Peppy had a daughter named Lucy, and that Vivian had died of a disease several years prior.

• Slippy's father, Beltino Toad. According to Slippy, Beltino works as an engineer for Space Dynamics, the manufacturer of the Arwing and many of the other vehicles the Star Fox team utilize. Beltino would later appear in-game for the first time in Star Fox Assault, and would later appear in Star Fox Command.

It's worth pointing that unlike Vivian, Beltino was mentioned in western ancillary SF64 material, that being both the official western Star Fox 64 website and the Star Fox 64 Official Player's Guide, where it states that he helped his son Slippy create the Blue Marine.

Takaya Imamura, who was in charge of Star Fox Command's characters and storyline, originally wanted to do a single linear narrative similar to the campaign in Star Fox Assault. Dylan Cuthbert, the game's director (and previously the programmer for the SNES Star Fox games), convinced him to turn it into a branching storyline with multiple different pathways and endings. According to Cuthbert, this approach was inspired by old 'Choose Your Own Adventure' books, such as the "Fighting Fantasy" series.

Katt Monroe, a female feline character who first appeared in Star Fox 64, had undergone a notable change in appearance from that game going into Star Fox Command, most notably now having black fur instead of pink. According to Takaya Imamura in a 2011 Nintendo Dream magazine interview, he changed her appearance to be more "fashionable".

Prior to Star Fox Zero, there were two attempts in previous installments to revitalize the concept of the Walker from Star Fox 2, or at least the idea of the Arwing transforming into a robot form, those specifically being Star Fox 64 and Star Fox Command, games that both aimed at preserving ideas from the then-long-lost Star Fox 2.

• For Star Fox 64, according to Shigeru Miyamoto in an interview at the end of the Star Fox 64 Official Player's Guide, he wanted to have the Arwing transform into "a human-type craft". This was rejected by other staff members of the SF64 development team. In response, Miyamoto told his team to come up with better ideas, and from there they created the Landmaster and Blue Marine for additional vehicles.

• For Star Fox Command, according to Takaya Imamura in an interview in 2007, the dev team experimented with having the Arwing and other spacecraft transform into robots, but this was ultimately dropped.

Star Fox Adventures primarily takes place on a planet filled with dinosaurs known simply as "Dinosaur Planet". It would return or be referenced in future games like Star Fox Assault and Star Fox Command, as well as "Star Fox Zero - The Battle Begins", a promotional anime released to commemorate the release of Star Fox Zero, but it would instead be referred to with a different name: "Sauria".

It turns out Rare had always intended Dinosaur Planet's real name to be Sauria, as leaked voice clips from the implied climax of the original Nintendo 64 Dinosaur Planet feature the Krazoa mentioning the name as they begin the alignment of the "Majestic Eight" planets to wreak havoc on the universe using the power of their god, the Quan Ata Lachu. An edition of "Ask Uncle Tusk" on Rare's old website revealed Dinosaur Planet's name to be Sauria as well.

The official Japanese Star Fox 64 guidebook reveals that Pigma Dengar, who became a subordinate of Andross, was effectively the real mastermind behind the creation of Star Wolf: he goated and manipulated Wolf into becoming its leader and also working for Andross as a means to combat the newly formed Star Fox team led by Fox McCloud, taking advantage of Wolf's supposed honorable, "magnaimous" side and also his prior rivalry with Fox's father, James McCloud. It is said that he manipulates the entire team behind the scenes in accordance to Andross' orders. It also reveals that Pigma had already been working underneath Andross during his time as a researcher at the Corneria Defense Force Scientific Research Institute. It's also revealed that both Pigma and Andross had custom engineered the Wolfens that the Star Wolf team utilize in their battles against the Star Fox team's Arwings.

In Super Smash Bros. 4, the trophies for Pigma and the Wolfen would reiterate this information, as would the official guidebook for Star Fox Command. The Star Fox 64 Official Player's Guide would similarly allude to Pigma being the root cause of Fox and Wolf's rivalry, claiming that, without his influence, perhaps they could have been friends in another timeline.

There is a target enemy in Star Fox Command known as "Bomber Bird". However, in the Japanese version of the game, it's referred to as サンダーバード (Sandābādo), which translates to "Thunderbird". This is undoubtedly a reference to the Gerry and Sylvia Anderson "supermarionation" television series "Thunderbirds" that inspired Shigeru Miyamoto to create the Star Fox series.

According to the official Japanese guidebook for Star Fox Command, the Solar Satellite boss fought on Solar was originally created by a scientist within the Anglar Army named "Genome", who reportedly developed it in secret using solar energy. This character does not appear anywhere in-game.

In the Japanese version of Star Fox Adventures, some of the dinosaur tribes have different localized names from their original names. For example, the CloudRunners are referred to as the クラウド族 (Kuraudo-zoku), which translates to "Cloud Tribe". The EarthWalkers are referred to as the アソーカ族 (Asōka-zoku), which strangely seems to directly translate to "Ahsoka Tribe". It's worth noting that the direct translation for "EarthWalker" in Japanese is アースウォーカー (Āsu-Wōkā); it's possible that アソーカ (Asōka) is meant to be a shortened, phonetic play on it, perhaps as the original name, directly translated, would be too difficult for Japanese audiences to pronounce.

In Star Fox: Assault's Sauria mission, Peppy curiously refers to the CloudRunner Tribe as just "the Cloud Tribe". This makes more sense when you factor in that that's what they're called in the Japanese version of Star Fox Adventures and thus was what the original script writers for Assault in Japan used as a frame of reference, and it appears that whoever was localizing the script for western audiences didn't bother to change it back to the original Rare name.

Funny enough, in Star Fox Command, Krystal pilots a spacecraft that is both shaped and named after the CloudRunners. In the Japanese version, it actually retains that name, クラウドランナー (kuraudorannā), which means that Command marks the first time Rare's original CloudRunner name was utilized in the Japanese version of these games.

The "Curse of Pigma" ending sees Fox and Falco head to a restaurant on the former's home planet of Papetoon to cope with their losses to their rivals, Star Wolf. The English text claims that Fox "lived as one already dead, barely eating or sleeping".

Looking at the Japanese script however, reveals a slightly different story:


A direct translation of this into English would be:


The original Japanese text effectively states the opposite of the English translation: Fox went on an eating binge while crying to cope with his losses to Wolf. This lines up more with the ending illustrations provided, which show Fox crying and eating at the same time.

The climax of Star Fox Assault sees the Great Fox, the Star Fox team's mothership and home base, destroyed in battle against the Aparoids. This is why in the next installment, Star Fox Command, it's been replaced with a smaller space carrier.

According to Takaya Imamura in a 2011 Nintendo Dream magazine interview, this particular model the Star Fox team rented is a common battleship type, which actually explains why other characters that appear throughout the story, such as Wolf and Lucy, are shown to have their own ships of the same model.

One of Star Fox Command's normal enemies, だるま落とし (Daruma otoshi) is modeled and named after the Japanese cultural toy of the same name, where the objective is to knock the colored center pieces off with a hammer without causing the "Daruma" doll at the top to completely fall over.

In the "Star Wolf Returns!" ending of Star Fox Command, it is said that after Krystal gained a new life as a bounty hunter named "Kursed" ("Krazoa" in the Japanese version) in another galaxy, she eventually came across Fox again on a planet named "Kew", although it's said that Fox doesn't recognize her.

The Japanese name for Kew is "キュー" (Kyū), which is essentially how "Q" is written in Japanese. This makes it more clear that Kew was actually named after Q-Games, Dylan Cuthbert's company that assisted in Star Fox Command's development.