News / Aug 20, 2026

Kamen Rider Heisei Phase 1: Fan Theories & Debates

Four recurring arguments define Heisei Phase 1 discussion: whether Decade wrecked its own crossover premise, what really happened to Hibiki mid-production, why Kabuto's second half divides fans, and which show is the "real" best starter. Here's what's confirmed and what's still just fan reading.

The most recurring Heisei Phase 1 debates are: whether Kamen Rider Decade's crossover premise was wasted, what actually caused Kamen Rider Hibiki's tonal shift partway through its run, why Kamen Rider Kabuto's second half is considered weaker than its first, and whether Kuuga or 555 is the better entry point. Some of these have documented, on-record answers from cast and crew; others remain fan interpretation. Here's each one broken down, with what's verified separated from what's still speculation.

Did Kamen Rider Decade waste its own crossover concept?

This is the single most argued-about entry in Phase 1. Decade's premise — a Rider who can travel between the alternate worlds of Kuuga through Kiva and wield all of their powers — is widely described by fans as one of the best ideas in the franchise's history, undercut by execution: the "worlds" Decade visits are distorted, off-model versions of the original shows rather than the real continuities, protagonist Tsukasa spends most fights borrowing other Riders' forms rather than fighting as himself, and the overarching plot involving the antagonist Narutaki is largely left unresolved in the TV series itself.

What's confirmed: the alternate-world structure and the unresolved Narutaki plot thread are matters of what aired on screen, not up for debate. What's genuinely split opinion: whether the crossover cameos and multi-Rider team-ups redeem those structural problems — that's where fan takes diverge, and it's the reason Decade shows up on almost every "most divisive Kamen Rider series" list.

What really happened to Kamen Rider Hibiki partway through?

Hibiki is the clearest documented case of behind-the-scenes change reshaping a Kamen Rider series mid-run. The show started as a slower, more atmospheric series about demon-hunting drummers, built around heavy location shooting and CG monster work. Rising production costs reportedly led to original producer Shigenori Takatera being replaced by Shin'ichiro Shirakura roughly a third of the way through the show's episode count, with new writers Toshiki Inoue and Shoji Yonemura brought in. Lead actor Shigeki Hosokawa has been quoted describing the post-changeover scripts as needing significant adjustment.

What's confirmed: the mid-series staff change itself, sourced to cast/crew statements and widely documented in franchise retrospectives. What's fan interpretation: exactly how much creative vision was lost versus how much the retool simply made the show more marketable — that verdict still splits long-time viewers.

Why do fans consider Kamen Rider Kabuto's second half weaker?

Kabuto's first half is broadly well-regarded for its stylish "Clock Up" combat and ensemble of native Riders. The common complaint about the back half (roughly episode 30 onward) is that plot revelations arrive in a rush without the buildup earlier episodes had set up, and the tone swings between comedy and heavier reveals in a way some fans find jarring. Unlike Hibiki, there's no publicly documented production shake-up behind this — it's generally attributed to pacing and structural choices by the existing creative team rather than an external change.

Label: this one is fan critical consensus, not a confirmed behind-the-scenes account — there's no on-record statement pinning it to a specific cause the way there is with Hibiki.

Kamen Rider Ryuki artwork — Ryuki's Rider-versus-Rider premise still divides fans.

Kuuga or 555: which is really the better starter?

Kuuga wins the recommendation most often because it was designed to need zero prior context. The counter-argument for 555 (Faiz) is that its darker, more morally ambiguous story about who deserves to hold power appeals more to viewers coming from modern seinen anime, and its pacing is tighter than Kuuga's slow-burn 49 episodes. Neither claim is really falsifiable — it comes down to what kind of story pace a given viewer wants first, which is why both shows keep landing in the top two on "best starter" lists rather than one clearly winning.

Bottom line

Confirmed by cast/crew record: Hibiki's producer and writing-staff change mid-series.
Confirmed by what aired: Decade's unresolved Narutaki plot and alternate-world structure.
Fan consensus, not documented cause: Kabuto's back-half pacing complaints.
Pure taste, no right answer: Kuuga vs. 555 as the best starter.

Kamen Rider Ryuki soundtrack album artwork — Ryuki's music is as debated as its ending.