* ContestedSequel: Although ''any'' of the Kamen Rider crossover movies[[note]]the winter movies; not counting the ''Super Hero Taisen'' movies[[/note]] would have a hard time following ''Film/KamenRiderXKamenRiderFourzeAndOOOMovieWarMegaMax'', which is generally considered the best of them, in particular, ''Movie War Ultimatum'' is often considered one of the weakest ones, seen as worse than ''Movie War Core''[[note]]which is disliked due to the massive [[ContinuitySnarl continuity snarls]] regarding ''Series/KamenRiderOOO'' - they wouldn't be so much of an issue if it wasn't for the fact that the ''Series/KamenRiderW'' half ''is'' canon to its respective series[[/note]], and the only movie that some consider worse is ''Film/KamenRiderXKamenRiderGhostAndDriveSuperMovieWarGenesis''.
** The main points of criticism are that the ''Fourze'' half is seen as an unsatisfactory ending for its respective show, and the ''Wizard'' portion is generally seen as even weaker.
* FanNickname: Parts of the western fanbase have jokingly called this movie [[WesternAnimation/MyLittlePonyFriendshipIsMagic Friendship is Magic]].
* HarsherInHindsight: The joke at the end about the Donut Shop owner being Yu Kamimura's real identity and Haruto's [[FreakOut response to the revelation]] can be kind of hard to watch knowing that said owner was portrayed by a closeted transwoman who retroactively stated that the Donut Shop owner is ''also'' a transwoman.
* RetroactiveRecognition: Hi there, [[Series/ShurikenSentaiNinninger MomoNinger]]!
* TheyWastedAPerfectlyGoodCharacter: During the truck chase scene, OOO pulls out the [=BraKaWani=] form [[TheBusCameBack for the first time since its debut]] in the ''OOO'' summer movie… and proceeds to jump off his motorcycle to hit the truck with his arm a few times before returning to his motorcycle, something he could have done with pretty much any other form, showcasing none of the combo's unique powers at all.
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