These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Ass Pull: Was it ever hinted at all in Climax Deka that Negataros had a time train?
Since when could Kiva enter time itself? Didn't Castle Doran simply have a tunnel to the past within it and not actual time travel capability?
Big Lipped Alligator Moment: Chou Den-O Episode Yellow ends with Owner vs. Station Master in fried rice golf, which was built up in the previous two movies.
Crazy Awesome: The Owner is a pure force of awesome with a lot of crazy awesome moments.
In Final Countdown, when the DenLiner is left stranded in the middle of the sands of time, his response is to grab a normal old bicycle, put on a pair of jogging shorts, and power the train with his own two feet. And it works.
Not to mention that he's even been shown jogging alongside the DenLiner, and keeping up! It's a greenscreen effect of course, but at one point he does that trick where you hold a cane in both hands and jump over it without letting go of the cane. It's not that easy.
Worth pointing out, the Owner's actor Kenjiro Ishimaru is a regular competitor on Ninja Warrior and does well despite being in his 50s. Crazy Awesome character and actor!
Creator's Pet: To some toku fans, the series itself is this, not so much because the show itself is bad, but because of how it's been turned into a Cash Cow Franchise, what with Toei releasing a movie every year, among other things.
Ensemble Darkhorse: The Taros proved to be the runaway stars of the show, prompting several musical releases and even their own Spinoff.
Ryotaro's actor changeover, which first appeared during Kamen Rider Decade's crossover with Den-O, lead some to speculate that this version of the Den-O World was simply another Decade Alternate Universe. However, it seems that Den-O is the only original Heisei universe to be featured in Decade, as evidenced by the Cho Den-O Trilogy.
Much Fanon attempts to explain why Hana herself wasn't/couldn't be Den-O, despite arguably being a better candidate than Ryotaro.
"Funny Aneurysm" Moment: During the release of Final Countdown, much lols were had over the subtitle 'Farewell Den-O', with jokes about the Cash Cow Franchise going on anyways despite the number of 'Final's used. Turns out it technically is the last Den-O movie... for Takeru Sato, who's moved on to other stuff.
Game Breaker: Climax Form, due to being a combination of Den-O's four main forms, and Wing Form, due to being a stronger basic form than the other four forms.
The idea of Zeronos' Zero Form cards erasing people's memories of the younger Yuuto seems a little more depressing considering that Yuichi Nakamura has left show buisness for good thanks to a Game-Breaking Injury. He has fortunately returned, however, and is returning to play as Yuuto in the upcoming Super Hero Taisen GP movie.
The younger Yuto Sakurai is played by the actor of a character from Kamen Rider Hibiki, as has been said elsewhere on this page. So basically, Yuichi Nakamura went from a show with Oni to a show with Owner.
The resemblance between Hibiki and Momotaros led to a fair bit of Memetic Mutation as well. Lampshaded in Decade when Kaito summons Momotaros to fight the riders in the Hibiki world.
During the Crayon Shin Chan crossover, Hana is the first to chastise Shinchan for his indifference to his mom being in danger from an Imagin. Turns out Hana has some mommy issues of her own down the line.
Den-O's habit of always going back to Feudal Japan in the movies is still continued through Ryotaro, through different means. Even better, Kintaros-posessed Ryotaro is basically a Palette Swap of Kenshin, and Momo!Ryo is basically an Expy of Sanosuke.
At the beginning of Final Countdown, the Taros don mascot costumes in order to patrol the city "inconspicuously" again. While Ura and Ryuu's costumes are befitting their nature (penguin and dragon, respectively) and Momo is wearing, ironically enough, a dog costume, what's Kin's costume? An elephant.note Don't see the connection?:The Taros are often compared to the Greeed, and the strongman of the latter, Gemel, is primarily designed as an elephant.
Not only does Climax Deka foreshadow an actual time policeman in the form of G Den-O, but the Badass Boast 'we are the badges' even foreshadows Eve, the artificial Imagin who only appears as a tiny badge-looking thing. Even better, the Rider Pass is inserted with a badge decal in Climax Deka, and another Pass has Eve's head glued to it to represent Eve in Episode Yellow.
Also worth noting is the final battle, where Kivat actually says "Hade Ni Ikuze!"
Ryotaro SUCKS as a fighter during most of the series, relying in the Taros to posess him so they can fight using his body. Then, in 2012, his actor goes into playing Himura Battousai.
Idiot Ball: In the climatic fight for Climax Deka, everyone transforms into their rider forms and the spare Imagin go into the fight to fend off the spare fangire around the room. What should have been an awesome fight is severely undercut by the problems of the scene.
Overall, the fight choreography is terrible. Zeronos is unable to even scratch the Clown Imagin due to it staying out of his sword's range, despite his sword being able to turn into a crossbow. For some reason, Ryutaros enters the fight without his Ryuvolver, but everyone else comes in with their own weapons; whenever the Taros swap out in their fight against Negataros, they also come away without their weapons and are never seen using them again in the film. The fangire they fight, too, never go out of their human disguises when fighting the Taros. The fight is only resolved because Zeronos becomes Vega Form, and Deneb is the only one who thinks to actually use a ranged final attack...and is somehow able to fire off a volley of these shots on one charge, destroying anyone not an ally or Negataros.
The fight against Nega Den-O itself, though inventive in that everyone swaps weapons around to counter the new ones being shown, comes to a jarring close in that, even when in Climax form, none of the Taros are able to match him. Things only turn around for them from the inclusion of Kiva, who, unlike in his own series, wasn't directed to the fight, but simply managed to ''find it'' while hunting down fangire.note For those not in the know, Kiva is led to fangire attacks he's unaware of thanks to a unique violin he has at his home, which mentally directs him to fights he isn't already present at. Wataru is entirely too passive to actively roam the streets randomly looking for fangire to kill.
Intended Audience Reaction: With older Sakurai shown to be Adorkable and younger Sakurai played by Kiriya, who else was expecting older Sakurai to be played by Hibiki just to seal the trifecta? Instead, the stand-in they put in the trenchcoat and hat is the same actor they bring back anytime adult Sakurai appears in the Den-O movies such as Episode Red.
Narm: The mooing sound made by Zeronos' visor when he turns into Altair Form. The sounds made by the Wing Form's swan-shaped visor are excused because of the form's over-the-top nature, but the mooing—especially when it's also done in Zero Form—is a bit much.
If you're human, you CANNOT say you at least came close to crying when Ura, Kin and Ryu disappeared.
Also, you're proabably jaded if the ending for Episode Red didn't move you.
Many of the arcs are like this. There's the time capsule arc, with a shot of the man sobbing as he holds onto the item he found in the time capsule, and the pianist arc where the silent pianist boards the DenLiner, forever stuck outside of time possibly until his comatose friend wakes up to the first arc where Ryotaro is able to get a thug to see his mother just as she dies in the hospital.
Kai's alteration of time causes Yuto to disappear and Deneb to be contracted to Ryotaro; unfortunately, we don't get to see Den-O Vega Form.Onigashima Battleship does include this, although it's Kotaro/New Den-O rather than Ryotaro.
Similarly, we never did get to see how the New DenLiner would fight, or even if it's cars are Transforming Mecha.
Visual Effects of Awesome: An understated version, but near any scene where someone is possessed by one of the Taros, Sieg or Deneb, the dubbing is damn near perfect, making it seem as though the person really is speaking the voices. The actors themselves do a great job of portraying the personalities of the Imagin possessing them.
They Changed It, Now It Sucks: Of course, some "fans" were already bitching because the series was very stylistically different from previous Rider shows, with giant monsters and mecha a bit more like a sentai show. Some got the hell over it, some still think that it ruined Kamen Rider forever.