- Acting for Two: As well as reprising his role as ZX, Shun Sugata is also serving as Fake Shemp for his enemy, the Badan Empire's Ambassador Darkness. This is eventually revealed to be because ZX is impersonating Ambassador Darkness.
- Dyeing for Your Art: In his blog post, Kento Handa remarked that he had to dye his hair in order to play Takumi Inui... a role he originated ten years ago.
- In Memoriam: This film is dedicated to Tohru Hirayama (producer from the original Kamen Rider series all the way up until Kamen Rider ZX) and Takao Nagaishi (who was the director for the first decade of the franchise's Heisei era).
- Milestone Celebration:
- This film commemorates the following celebrations for the franchise — 40 years for Kamen Rider X, 35 years for Kamen Rider: Skyrider, 30 years for Kamen Rider ZX, 25 years since Kamen Rider BLACK RX's finale, 20 years for Kamen Rider J, 15 years for Kamen Rider Kuuga, 10 years since Kamen Rider Faiz's finale, and 5 years for Kamen Rider Decade and Kamen Rider Double.
- The film also seems to celebrate how there are an equal amount of primary Showa and Heisei riders, as seen with Kamen Rider Fifteen.
- Name's the Same:
- This movie features three Ichigos — Kamen Rider #1, Gaim Strawberry Arms, and Toq #1. Ichi and Go by themselves is 1 and 5, put it together and you get the number of Showa Riders and Heisei Riders facing off. Acknowledged when the ToQgers show up and Raito offers to lend his power to Hongo as a "fellow #1"
- Keisuke's granddaughter is named Mari, which presumably rubs a sore spot with Takumi for very good reasons.
- When Tsukasa goes to Fuuto, Kaito Kumon offers to go with him. This isn't the first time Tsukasa has worked alongside a Jerkass named Kaito...
- Old Shame: Hiroshi Fujioka was not happy with how he was portrayed here. So much so that he helped with rewrites in 2016 film Kamen Rider Ichigo to get his character right.
- The Other Darrin: Tomokazu Seki voices the Badan Empire's incarnation of the Great Leader following the passing of his original voice actor, Goro Naya, in 2013.
- Production Foreshadowing: We learn in the end that Murasame Ryo and Ambassador Darkness just happen to resemble each other because they actually are the same guy. Guess what we learn about Mai and the Girl at the Beginning later.
- Reality Subtext: Kamen Rider Den-O and Daigo of Zyuden Sentai Kyoryuger have both been accused of being the Spotlight-Stealing Squad (Daigo within his own show at least, while Den-O has had one movie or cameo after another). So what happens when they're in the same movie? Argue over who gets to be on top, of course. The combined mecha, that is.
- Recycled Script: The reason why the Riders are killing each other being because "dying" actually sends them to another dimension, alive and well, so that the villains think the heroes are all dead and then bring out their super-weapon into the open, unaware of the Big Damn Heroes incoming from the few survivors opening up that dimension... looks like Hongo directly ripped some pages off Tsukasa (and Captain Marvelous) during the events of Kamen Rider X Super Sentai Superhero Taisen. Well, that's half the reason why...
Trivia / Heisei Rider Vs Showa Rider Kamen Rider Wars Featuring Super Sentai