Episode 21 came at the request of Kiita Komagine wanting to play a bad guy for once.
Episode 29 came about when Ryo Sekoguchi mentioned that he wanted to play tennis, which led to the creation of the veryThe Prince of Tennis-inspired Tennis Wald.
Shintarō Asanuma (Juran) admitted that when his agency told him he landed a role in the series, he was under the impression that his audition was for a Monster of the Weekas usual, only to be shocked to learn later on that not only was it for a leading role instead, but he would be voicing the Red warrior himself, a major protagonist role usually reserved for live-action actors.
Similarly in the same interview Kiita Komagine (Kaito) revealed he wasn't informed he'd be the only human of a core team of mostly robot characters until he was told he had passed the audition.
According to Ikue Sakakibara (Yatsude), she was simply given the Geartlinger and was told to strike a cool pose in front of an explosion on set on the very first day of filming, not knowing what it was for. This eventually became the Imagine Spot in the first episode of her being a Zenkaiger alongside Kaito.
Cast the Runner-Up: Ryo Sekoguchi (Stacy) initially auditioned for Kaito. While he lost to Kiita Komagine, he apparently impressed the producers enough for them to create a whole new character to cast him as.
Episode 7 featured Kiita Komagine doing a backflip, something that he managed to learn in two days of practice.
The show often has Atsuki Mashiko show off his singing and dancing prowess during Zocks's scenes from time to time.note He's a part of the J-pop idol group known as GENIC, who has done the ending for the final season of Fruits Basket.
A picture of Zenkaizer was leaked before the official reveal, due to being used to promote a DIY claw machine toy that came with a kids' magazine, followed shortly by someone leaking the production notes and concept art for all the characters online.
Averted for Stacy, much like Yodonna from the previous series. While leaked magazine scans preview that the Zenkaigers will be facing their predecessor Sentai teams in the coming episodes, Stacy's presence and involvement with summoning them wasn't alluded to at all until official reveals and On the Next episode previews came out. And even then, his Ranger form as Stacaesar was also not leaked until the official reveal came out the week before his debut. What was largely foreshadowed in that month's issue was instead a silhouette of the upcoming Sixth Ranger.
Twokaizer himself was leaked a week before his official reveal through a Toys "R" Us product listing.
Super Twokaizer and Super Zenkaizer forms, also Twokaiser SD form and how both of them combine to form Zen Kaijuu Oh based on both V-Rex Robo and Dragon Caesar, were initially leaked through product licensing listings before images were leaked months later (still before official announcements) through magazine scans.
Creator Backlash: Kiita Komagine admitted that he wasn't particularly fond of episode 5, mostly due to how physically demanding the sushi set-up was, along with the cold weather.
Voice actress Satsumi Matsuda voices Twokai Ricky, one-half of the Goldtsuiker twin brothers.
Along with the male Hikoboshi Wald, Soichiro Hoshi also voiced the female Orihime Wald.note Assistant producer Matsura suggested that both Orihime and Hikoboshi Wald should be voiced by the same voice actor to tie in with the theme of Tanabata.
Descended Creator: Daiki Ise, who sings the theme song for the spinoff Introducing ZenkaiRed!, portrays ZenkaiRed.
The Zenkai Red Spin-Off was devised in response to the skeptical reception to Zenkaiser, who was originally conceived as a red warrior before his color was changed to white/rainbow.
In Episode 19, the last attempt Stacy makes to try to reawaken Kaito's parents from their stasis is to act like him. Stacy's actor, Ryo Sekoguchi, originally auditioned for Kaito.
Episode 32 further alludes to this by Sekoguchi playing Kaito in Stacy's body (albeit dubbed with Komagine's voice).
Masaya Fukunishi eventually took over the voice of Gege from Episode 25-onwards after Tatsuhisa Suzuki stepped down from the role.
Koh Enomoto substituted for Yumeki Uenoyama as Young Kaito in Episode 40.
Playing Their Own Twin: Kousei Sutou portrays both of the Goldtsuiker twins when they were human.
Playing with Character Type: Takuya Sato is primarily known for his Nice Guy roles, quite a few are noted to be particularly handsome and/or charming. Vroon is a Nice Guy through and through, but he's also quite the clumsy nerd who's more known for his curiosity rather than his looks (he is a Kikanoid after all).
Kiita Komagine (Kaito) stated at the press conference that he watched all of the series from Hyakujuu Sentai Gaoranger to Mahou Sentai Magiranger when he was a child (hilariously enough, two series that two of the Zenkaigers are based on).
Yuki Kaji (Gaon) posted shortly after the press conference that it was a dream for him to become a Sentai hero and particularly loves the red rangers (but hilariously stated that he'll love yellow rangers from now on). In a separate tweet, he mentioned that he watched Kousoku Sentai Turboranger, Chikyuu Sentai Fiveman, and Choujin Sentai Jetman as a child.
Yume Miyamoto (Magine) stated that she was inspired by Mika Kikuchi's portrayal of Umeko/DekaPink, wanting to become a pink ranger as she grew up.
Takuya Sato (Vroon) also stated in a blog post that it was a dream of his to become a Sentai hero and appreciated the chance to become one through being a voice actor.
Ryo Sekoguchi (Stacy) stated in an interview that he's a fan of Mahou Sentai Magiranger. Fittingly enough, it's one of the Sentai Gears he uses in his debut episode.
Satsumi Matsuda (Twokai Ricky) is a major Tokusatsu geek, having the Survive Decks as her Twitter header and co-hosting a dedicated blog with her twin sister.
A particular Kikainoid helmet with a brunette Beehive Hairdo was often recycled to represent multiple different female Kikainoids, usually the Love Interests of humans in moments of Interspecies Romance shown.
The Walds all use the same base body of a Kudaiter. Similarly, the Great Walds all use the same Kudaitest base body while reusing their original Wald forms' unique armor/weapons.
Recycle Wald is quite literally a complete recycle of Gomi Wald, with an added "recycle" logo.
Hidokei Wald is kitbashed from Mahiru Wald's head and Retro Wald's Toki wo Modosword.
Sanjo from #38 is basically a spare Juran suit with a wig and beard tacked on.
Episode 46 is full of this:
Ninjin Wald is a recolored Daikon Wald.
The carrot-fied Zenkaizer uses a modified Zenkai Red suit.
Sapphire Wald is a recolored Daiya Wald.
A number of Kiramai Stones were used as generic gemstones created from Great Sappire Wald's influence.
Kōmori Wald is a recolored Sakasama Wald.
Ijirudestroyer IV is a recolour of Stacy's Battle Caesar Robo with Battle Caesar Robo II's head. Its cockpit is reused from its basis' first two iterations.
According to this interview, Stacy wasn't actually planned from the start, but Ryo Sekoguchi's audition impressed the producers to the point where they settled on creating a whole new character for him.
The lack of usage for certain mecha such as ZenkaiOh JuraMagine, VrooGaon, Super ZenkaiOh Juran, Super TwokaiOh and Zenryoku ZenkaiOh was allegedly due to a lack of full costumes made for them, which meant they could only be rendered in Stock Footage CGI. This is also similarly why New Kudaitests were made to be Godzilla Threshold and unable to be mass-manufactured.
Due to Tatsuhisa Suzuki stepping down from the role in August 2021 (originally him posting it as due to health concerns but later revealed to be having an affair), Gege was made The Voiceless from episode 22 to 24, instead talking in Voice Grunting from stock audio clips of his voice while having the other members of the Tozitend relay his intentions to the audience. Episode 25 (the Recap Episode) was used to introduce his replacement voice actor Masaya Fukunishi into the role.
According to staff comments the main reason there was so many suit characters in this particular season, especially the Kikanoids which filled out 4/5 main team spots and a significant number of civilians is because of the Covid pandemic as suit characters count as "Masked" as far as filming restrictions on how many unmasked actors could be on set and how close they could stand to each other were since the helmets fully conceal their face.
Refitted for Sequel: The naming convention for the parallel universes ([Something]topia) was earlier considered for Zyuohger (the Zyumans' home of Zyuland would have been named Zyutopia) but was dropped to avoid comparison with other works.
Mashin Sentai Kiramager: Juru Atsuta/Kiramai Red, Tametomo Imizu/Kirmai Yellow, Sena Hayami/Kiramai Green, Shigeru Oshikiri/Kiramai Blue, Sayo Oharu/Kiramai Pink and Takamichi Crystalia/Kiramai Silver.
Serendipity Writes the Plot: A minor case. The Geartozinger prop's failure to rotate its barrel when its handle is cranked ended up being such a signature feature of it that in the Memorial Edition of the toy it was worked into and marketed as a key feature, unlike the original release version which was still able to rotate its barrel.
Throw It In!: The cast tends to ad-lib quite a bit, leading to jokes that the script is "30% script, 70% ad-lib".
Zocks's dancing during his sea shanty in episode 8 was entirely of Atsuki Mashiko's creation.
Shintaro Asanuma stated in the June 18th episode of Kamen Radiranger that the "maybe" in episode 8 was an ad-lib.
Yuki Kaji tends to adlib during comedic moments, such as Gaon's "heavy" line in episode 10 and his "sarabye" in episode 11.
Ikue Sakakibara improvised Yatsude's poor attempt to defend herself (heavily inspired by her Geartlinger scene in Episode 1) in Episode 29.
Zenryoku ZenkaiOh was not originally planned from the start. When the request to create it came through, it led to the toy engineers having to figure out how they could combine all four of the existing DX ZenkaiOh toys into one single robot, something they were never designed to do. The result was the Zenryoku Zenkai Cannon.
Troubled Production: Tatsuhisa Suzuki's sudden hiatus in early August 2021 left the crew no choice other than to make Gege The Voiceless from Episode 22 to 24. He was eventually replaced by Masaya Fukunishi.
Kiita Komagine revealed in an interview that he tried to portray Kaito with a much higher voice as he was Playing Against Type from his more serious roles. Head director Shojiro Nakazawa told him that he didn't have to force himself to do a higher voice since he already had the personality down, so he settled on his natural tone of voice.
Both Shintarō Asanuma (Juran) and Takuya Sato (Vroon) also auditioned for Gaon.
Zenkai Magine's Concept Art had her "loincloth" mostly black down the middle, suggesting it was meant to either accentuate or blend into her Leotard of Power design, while her shoulders had gold trimmings.
Originally, both Zenkaiser and Zenkai Juran were supposed to be red. But Junko Komura didn’t want two reds on the same team, and suggested changing Juran to green. Instead, they simply decided to make Zenkaiser white.
An attempt was made to design Armors for the Sentai Gears, but came into difficulties to differentiate between teams as some share the same theme, so they instead opted for techniques. A few Gears do retain elements of this, such as Twokaizer's form changes as well as the super modes.
Having the Zenkaigers summon the past Sentai was considered, but that ability was given to Stacy to avoid having the summoned warriors steal the spotlight. The Zenkaigers ended up having such a power much later into the show anyways, thanks to obtaining the Zenryoku Zenkai Cannon, however the Rangers they can summon are grouped by their themes rather than their original teams. note With an exception being granted for an instance in the team-up special, where the cannon ends up summoning the core Dekarangers with one summon.
Word of God: Producer Shirakura puts Juran's age in the 40s, while the others are in their 20s.
When previews showed that only RyuseiOh would be appearing instead of the full mecha, Ei Hamura/Tenmaranger claimed on Twitter that it was because the person who summoned it didn't have a strong enough will to summon all of it.
Shintaro Asanuma puts Juran at 45 years old, as it is the anniversary number of Zenkaiger (and coincidentally the same age as himself).
Working Title: As revealed by Tom Constantine, a proposed title for the series was Sentai Sentai Sentaiger. The name "Sentaiger" ended up being used by the Geardalinger as the generic sound used when activating Sentai Gears for previous teams.
Writing Around Trademarks: Kinoko Wald/Warudo almost has the same name as the country Kinoko/Mushroom World in Super Mario Bros., but spelt as such likely to prevent any potential copyright issues. Likewise, the parallel world he representsnote A similarly mushroom-dominated dimension also does this by being named Kinokotopia. This was even lampshaded by a Mario fan in a Tweet.
Shintaro Asanuma (Juran) previously voiced the Monster of the Week Sambaba in Doubutsu Sentai Zyuohger (though it is hard to tell since he is using a much higher voice than Juran). Notably, out of the Zenkaigers, he is the only one who had a previous role in Sentai.
Joji Nakata (Boccowaus) is very well-known in the Sentai sphere, best known for his role as Great Professor Bias in Choujuu Sentai Liveman as well as some other major villain roles. He lampshades this in this tweet.
Kenji Nomura (Barashitara) has previously voiced a few Sentai villains, with his previous general role being Beast Baron Cobolda in Kyūkyū Sentai GoGoV.
shortly after the press conference that it was a dream for him to become a Sentai hero and particularly loves the red rangers (but hilariously stated that he'll love yellow rangers from now on). In a separate tweet