Refitted For Sequel / Anime & Manga

• Gundam:
  • Numerous mobile suit designs and other things cut from the original Mobile Suit Gundam later made it into Mobile Suit Zeta Gundam and other sequels. Most notably one of the major characters, Princess Mineva, was originally going to be Degwin Zabi's youngest child in the earliest drafts of the original series (then named Miharu, which wound up being used for a completely different character) instead of his granddaughter.
  • A lot of concepts from the "Tomino Memo" — supposedly Yoshiyuki Tomino's full 52-episode plan for Mobile Suit Gundam — have been refitted here or there. For example, the Memo featured Kusko Al, Degwin Zabi's Sexy Secretary who spies for Zeon while seducing Bright Noah; Tomino's novelization of the series reworks her into a Newtype pilot.
  • A large number of ideas from a planned 1983 Hollywood film adaptation of the original series eventually made their way into later shows, including the Mobile Suits using a motion capture interface, the protagonist being forced to fight his brother who has been brainwashed by an evil AI, the protagonists gathering a Magnificent Seven Samurai-style team to take down the bad guys, one of the pilots being a former baseball player and a supercomputer hidden inside an asteroid fortress manipulating the war. This even extends to the staff, as Syd Mead, who was recruited as a production designer, went on to work on ∀ Gundam.
  • There were at least a couple of plans during the first season of Mobile Suit Gundam: Iron-Blooded Orphans that were initially scrapped, but then subjected to this for the second season, namely Tekkadan getting ostracized for being amoral mercenaries, and receiving a catastrophic number of casualties in the end game. Also, plans for offing Lafter and Norba in the previous season were repurposed later on.
  • Yoshiyuki Tomino's earliest concept for Mobile Suit Gundam was basically Jules Verne's Two Years' Vacation/Adrift in the Pacific in space. Four years later, Sunrise repurposed the idea (with mecha) to make Ginga Hyouryuu Vifam, where Tomino gets credited for creating the original draft.
  • The original draft for Mobile Suit Gundam Unicorn had it take place around Moon Moon, with Join Banagher searching for help outside the colony to help repair it and running into a disguised ship carrying Mineva, causing Moon Moon to be drawn into a conflict between Neo Zeon and Londo Bell. While this was scrapped for Unicorn, the concept would be later reworked as Mobile Suit Moon Gundam.
  • Mobile Suit Gundam SEED was originally conceived as taking place in the late Universal Century timeline sometime after G-Saviour (the Mobile Suit design sketches for both look uncannily similar, though it's not as obvious watching them on screen, thanks to the latter's infamously crude 90s CGI) before being reworked as a retelling of the original series in an Alternate Continuity. Gundam: Reconguista in G revisits this concept, building on many of G Saviour's ideas such as a post-federation Earth and the fallout of a massive food crisis, while featuring a main Gundam using interchangeable backpacks almost identical to the Strike Gundam.
• In Pokémon: The Series, the footage from the cancelled "Team Rocket vs. Team Plasma" two-parter in Best Wishes - where the Relic Castle's mechanism is activated, revealing the Meteonite - was reused for the scene in Best Wishes Season 2 when the Abyssal Ruins are activated to uncover the Reveal Glass. Team Plasma's intended goal of causing Pokemon to go wild and leave their trainers was also later used in the Episode N story arc, with Colress' device used to do so in place of the Meteonite.
• In the planned Mythos arc adaptation for the 1979-80 Cyborg 009 anime, Helena would have been replaced with a more mythologically-accurate Expy named Artemis. The show was cancelled before the Mythos arc could be adapted, but Artemis later made a proper debut in the 2001 anime.
• In FLCL, there was apparently an unused idea to reveal that the town of Mabase was actually on Mars. FLCL Alternative, originally designed as a Stealth Prequel, ties that idea into its final episodes, which feature Haruko winding up on Mars with some human colonists. Whether or not it's still a prequel or an Alternate Universe depends on interpretation.
• Ghost in the Shell 2: Innocence is an expanded version of the Robot Rondo chapter from the original manga that the first movie left out.
• Dragon Ball has an unusual instance of this with Gogeta, the fusion of Goku and Vegeta. Akira Toriyama originally planned on introducing the character during the Buu Saga, but then he discovered that Toei was already making a movie whose main selling point was the grand debut of Gogeta. Not wanting to step on any toes, Toriyama came up with an entirely different method of fusion that produced an entirely different fused character, Vegitto. A couple of decades later, Toriyama penned the movie Dragon Ball Super: Broly and decided to have Goku and Vegeta fuse in order to fight the titular enemy; so while Gogeta was an "official" part of Dragon Ball lore, he didn't become canon until 24 years after his debut.
• Little Witch Academia:
  • Lotte's parents being the owners of a magic shop/cafe was originally conceived for the first short film, only to get scrapped due to time constraints. The TV series revisits and realizes this idea in its 16th episode.
  • A Gadgeteer Genius student who combined magic with technology was originally planned for the first film but was ultimately scrapped due to the team finding her to be unnecessary. The idea would later be realized in The Enchanted Parade in the form of Constanze.
• In Lupin III: Stolen Lupin, Becky Lambert was originally going to be part of a crew of female thieves. However, this idea was scrapped due to worries about it seeming too similar to Charlie's Angels: Full Throttle, which was released while the special was in development. Despite this, the staff would later revisit the idea of a gang of female criminals with the Bloody Angels in Lupin III: Angel Tactics the following year.
• A scrapped idea present in the original proposal for Neon Genesis Evangelion was an aerial battle involving high altitude gear for the EVAs. This idea was eventually used for the opening of the third Rebuild of Evangelion movie many years later.
• Sailor Moon; One of Naoko's concepts was for Ami/Sailor Mercury to be a cyborg. She revisited that idea with Hotaru^note Only in the manga and Sailor Moon Crystal..
• Science Ninja Team Gatchaman: One rejected idea for the show's final episodes would have involved Berg Katse being demoted after their unmasking and then aiding the Science Ninja Team, this was dropped once the true natures of Katse and Leader X were finalized, in addition to the idea to have the storyline center around Joe slowly dying. A similar concept would be used in Gatchaman II, with new Galactor commander Gel Sadra betraying X after he kills her mother Dr. Pandora, and then leading the Science Ninja Team to Galactor headquarters.

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