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* DummiedOut: Data exists for a fully-functional Zebesian enemy, rather than the hologram from the tutorial or the cyborgs on the Bottle Ship. One can even be seen in the game's trailers.
* FranchiseKiller: While the game received decent critical reception and sold as usual in Japan, ''Metroid'' fans were viciously negative towards it, leading to poor word-of-mouth and low sales in the West. Creator/YoshioSakamoto would temporarily step away from the series as a result of the backlash, which when combined with Creator/RetroStudios choosing to develop ''VideoGame/DonkeyKongCountryTropicalFreeze'' rather than return to the ''Prime'' series, caused the franchise as a whole to go on a six-year hiatus after a decade of almost yearly releases. The next entry in the franchise would be a spin-off (2016's ''VideoGame/MetroidPrimeFederationForce''), followed by a remake the following year (''VideoGame/MetroidSamusReturns''). It would take until 2021, eleven years after ''Other M''[='=]s release, for the franchise to get a new original installment with ''VideoGame/MetroidDread''.
* KeepCirculatingTheTapes: The game was ported to the Wii U eShop among other Wii games. However, it was lost with everything else following the eShop's closure in 2023. Copies of the game however can be found at affordable prices though.
* MagnumOpusDissonance: Yoshio Sakamoto viewed the story as the best in the franchise, and as something that finally made Samus a fully-developed, well-rounded and sympathetic character, stating in interviews that he even cried when he saw some of the scenes of the game for the first time. In contrast, the story is the biggest reason why some fans vilify the game, with a few even calling it a disgrace to Samus' character. He also seems significantly more proud of the game overall, even with its mainly western backlash and disappointing sales figures, and has even gone on record in the years following its release that he still would not change a single thing about the game, gameplay or story wise. Although when ''VideoGame/MetroidSamusReturns'' was announced at E3 2017, while he reiterated that he still had made what he wanted to make, [[https://kotaku.com/metroid-samus-returns-feels-great-to-play-1796236226 he said]] the criticisms had given him the ability to look at her from another point of view, and to reconsider what to show about her.
* TheOtherDarrin: Samus is on her third voice actress, Jessica Martin. Fourth, if you factor in that Samus' death scream in ''Prime'' was actually done by Vanessa Marshall, while the rest of her sounds were done by Jennifer Hale.
* WhatCouldHaveBeen: At GDC 2010, Sakamoto admitted that, due to his demand for a single Wii Remote control scheme and his inexperience with 3D game design, one of his initial ideas was to make 2D sidescroller like previous entries (though the way he phrased it had people believe [[http://web.archive.org/web/20190218161412/https://kotaku.com/metroid-other-m-might-have-been-on-rails-if-not-for-t-5491158 he wanted to make it a rail shooter]]).
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