Unexpected Character / Kamen Rider Zi-O

Since many actors from previous seasons return in this one, this was bound to happen.

General examples

• Many people were awaiting the return of Tsukasa Kadoya/Kamen Rider Decade, but nobody could've seen him becoming a recurring character, complete with a new magenta-coloured Decadriver that allows him to not only turn into Kuuga through Decade, but also into W through Zi-O!
• Like Decade, everybody expected Kimito Totani to reprise his role as Daiki Kaito/Kamen Rider Diend, but like Decade, nobody expected that his Diendriver would get a cyan-coloured upgrade just like Tsukasa's Neo Decadriver, allowing him to summon more Riders from Accel onward.
• Everyone expected Kamen Rider Woz to be well…Woz. They were right in a way, but almost no one expected the Woz in question to be Woz from another timeline. This also made it more unexpected that Black Woz would become Kamen Rider Woz after all.

Ex-Aid Arc

• It was a big surprise in Ex-Aid tribute arc that Heure’s Time Mazine would incorporate Captain Ghost.

Fourze/Faiz Arc

• While Gentaro was expected to be a Fake Shemp, what wasn't expected was that Sota Fukushi was still able to record some dialogue.
• Chuta Ohsugi was a really unexpected character since unlike the other returning actors at the time, he isn't a Rider at all.
• What was also unexpected were the unannounced appearance of Nezu and Kong from Movie Wars Ultimatum (two of the characters from Fourze's modernized take on Ishinomori's Inazuman manga).

Wizard Arc

• Kosuke Nitoh, aka Kamen Rider Beast was also a surprise since his actor had not reprised his role even once after Wizard's run ended with Kamen Rider × Kamen Rider Gaim & Wizard: The Fateful Sengoku Movie Battle.

OOO Arc

• Kuroto Dan, returns, and as Another OOO of all things.
• Eiji's return was unexpected as well, as they manage to keep it a secret until the next episode promo.
• The Time Jackers pull out another custom Time Mazine, this time made by combining with Castle Doran.

Gaim Arc

• Sougo gets help from none other than… himself from 3 days into the future.

Heisei Generations FOREVER

• The Master of Fumen, an Ascended Extra who presents Sougo the W Ridewatch as the only returning character of Kamen Rider W.
• While Kamen Rider Den-O, the Taros and DenLiner crew appear as expected, the most unexpected surprise return during the film’s premiere is Takeru Sato finally reprising his role as Ryotaro Nogami/the original Kamen Rider Den-O ever since a decade after Saraba Kamen Rider Den-O: Final Countdown. Takuya Mizoguchi plays a de-aged Ryotaro in the Cho Den-O Movie Series and Momotaros himself plays the role of Den-O in crossovers due to Satoh’s strict agency and Toei being unable to afford him.
• To a lesser extent, Toshiki Kashu and Takamasa Suga both reprise their voice-only roles as Shouichi Tsugami/Kamen Rider Agito and Shinji Kido/Kamen Rider Ryuki for the first time since the former made a brief cameo in Kamen Rider Decade: All Kamen Riders vs. Dai Shocker while the latter had not reprised his role aside from video games. Then they eventually appear in the series proper in their respective arcs.
• Riku/the original Kuuga as a corpse, possibly as an Excuse Plot to provide a source for Kuuga’s powers.

Ryuki Arc

• While Shinji’s return was expected because of Heisei Generations FOREVER, no one expected Daisuke Okubo to return since not only is he not a Rider like Chuta Ohsugi, but he came from a series that was from over 15 years ago.
• Everyone expected for the Another Rider to be Another Ryuki, but no one expected it to be Another Ryuga instead, which makes this the first non-primary Another Rider and just as surprising is the return of Dark Shinji is a movie villain just like Ryuga.
• On that note, an evil Mirror World Sougo/Zi-O, was only revealed in the episode 21 preview for the Ryuki Arc.

Rider Time Ryuki

• No one expected Kamen Rider Abyss to appear as he is not part of the original 13 Riders.

Kikai Arc

• Most expected Kamen Rider Kikai to be portrayed by a former Super Sentai actor who played a Ranger, but instead, he is portrayed by Jingi Irie who portrayed the reboot version of Kikaider and played Zamigo Delma, a Sentai villain from Kaitou Sentai Lupinranger VS Keisatsu Sentai Patranger.

Blade Arc

• Kazuma Kenzaki/Blade and Hajime Aikawa/Chalice were expected, but no one expected Amane Kurihara reprised by Hikari Kajiwara, who is also not a Rider like Chuta Ohsugi and Daisuke Okubo. It turns out she gets turned into Another Blade.

Agito Arc

• Shouichi Tsugami/Agito was expected but no one predicted Takahiro Omuro and Mana Kazaya returning with the latter being reprised by none other than Rina Akiyama for the first time since the end of the original series. The insert song "Believe Yourself" also makes a reappearance in #32.

Hibiki Arc

• Tomizo Todayama aka Kamen Rider Todoroki appears, but Kyosuke Kiriya, who is also The Scrappy in the original series and an unpopular character in the fandom, also makes an unexpected appearance, especially with the latter's actor being more well-known for portraying Yuto Sakurai/Kamen Rider Zeronos instead. What becomes more surprising is that he succeeded Hitoshi Hidaka as the new Kamen Rider Hibiki.^note Hitoshi’s absence and Asumu not being the new Hibiki are likely a case of Real Life Writes the Plot. Shigeki Hosokawa, Hibiki’s actor, had been fired prior to Zi-O while Rakuto Tochihara, who played Asumu Adachi, retired from acting in early 2018.

Kiva/Ginga Arc

• Garulu’s human identity Jiro and Yuri Aso, especially with the latter’s character having passed away by the 2008 era of Kiva‘s timeline. Turns out the latter is playing a new character instead, referred to only as “Mrs. Sailor”.
• Kamen Rider Ginga himself, and the fact that his own Future Rider arc is even combined with Kiva's, not to mention being voiced by Tomokazu Sugita, who was known to have voiced Kivat from Kiva itself instead.

Kabuto Arc

• Arata Kagami/Kamen Rider Gatack, as his return was thought to be impossible due to him leaving his agency.
• The sight of Sou Yaguruma/KickHopper and Shun Kageyama/PunchHopper is also surprising especially with the latter who is actually dead in the original series before he could fully become a Native Worm.

Den-O Arc

• The younger Yuto Sakurai/Kamen Rider Zeronos in-person, due to the fact that complications might arise since his actor Yuichi Nakamura had also reprised his earlier unrelated role of Kyosuke Kiriya/Kamen Rider Hibiki II.

Another Zi-O II Arc

• Due to being a CGI creature instead of a proper suit, no one was expecting Another Kuuga to show up among the Another Rider army in the Bad Future.

Movie Riders Arc

• No one expected Michal Minato/Kamen Rider Aqua from Movie War Mega Max to return at all, with some even being convinced that Toei had forgotten him until now.
• It also features the unexpected debut of Katsumi Daido/Kamen Rider Eternal from Kamen Rider W Forever: A to Z/The Gaia Memories of Fate.

Over Quartzer

• It's a recent tradition for the summer movies to feature a Dark Rider, but Over Quartzer not only has three movie Riders which are known as Quartzer, but they're all based off "lost Heisei Riders", AKA Rider productions in the Heisei era but aren’t officially called Heisei, known as Kamen Rider Barlckxs^* Both Black and Black RX are the only mainline Kamen Rider to have a direct sequel series, as well as being the series that straddles the Showa Era and the Heisei Era due to the shift occurring ten episodes into RX., Kamen Rider Zonjis^* Shin, ZO and J all debuted as movies during the Heisei era. However, as Ishinomori was involved in their creation and their tone matches up with the Showa era Riders they're counted by fans and now Toei themselves as Showa Riders., and Kamen Rider Zamonas^* Amazons isn't counted among the Heisei era of Riders due to being an adult aimed side-series..
• Absolutely no one expected the Drive tribute would be merged with the summer movie, complete with the appearances of Gou Shijima/Kamen Rider Mach and Krim Steinbelt.
• In prison Sougo gets visited by Kamen Norider.
• The movie features appearances by Manga!Godai, Zangetsu Kachidoki Arms, Kamen Rider G, Kamen Sentai Gorider and Kamen Rider Brain in the final battle summoned by Zi-O Oma Form.

Final Arc

• No one expected Chase/Mashin Chaser to appear in the series especially since we already got two Drive representatives in Over Quartzer.
• Due to originally appearing in a .5 gag episode, no one expected Kamen Rider Tsukuyomi to be present in the main series at all. Surprise!

NEXT TIME

• Akira Date's return was a huge surprise for everyone since he hasn't reprise his role since Kamen Rider × Super Sentai: Super Hero Taisen, not to mention that he was replaced by Shintaro Goto as the user for Birth in his own series.
• No one expected Another Diend to be the Big Bad of the film.

Reiwa the First Generation

• While Another Zero-One was expected in some capacity, what was not expected was an Another Rider based on Ichigo himself.

Final Stage

• The surprise return of Hiryu Kakogawa, and him becoming Another Oma Zi-O using the power of the Showa Riders!
• Amazon Alpha and Amazon Omega from Kamen Rider Amazons as well as Ichigo, Nigo and V3 from The First and The Next all return in the stageshow.
• Tsukuyomi getting her own Woz called Red Woz.
• Zi-O getting a Woz Ridewatch and becoming Kamen Rider Zi-O WozArmor.

Zi-O vs Decade/Decade vs Zi-O

• Masahiro Inoue returning as Decade, since he had previously announced that Zi-O would be the last time he reprises his role as Tsukasa.
• Diend returning was also expected, but not Kamen Riders Kivala and AR!Kuuga.
• Tsukasa getting an upgraded Complete Form, since he didn't use it in the series proper. But this one also includes the abilities of the Secondary Riders, as well as Kamen Rider Zero-Two!
• Sougo using a Saber Ridewatch!
• Who was that masked figure orchestrating the death game? None other than Narutaki!

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