* ActorSharedBackground: The Osaka-native Creator/MaoIchimichi is the voice of Anzu from the Osaka team in ''Gantz:O''.
* CreatorBreakdown: Before Gantz, the series creator Hiroya Oku made a fair bit of money with his first manga Hen, a romantic comedy, and invested most of it into a 3D modelling software in order to create Zero One, a manga that would be innovative at the time by blending hand-drawn and CG panels. However, since 3D modelling was not commonplace to the general public yet (it was 1999), the results ended up being... [[UncannyValley weird]], to say the least. It's said that the failure of Zero One influenced into the utter cynic and pessimistic atmosphere of Gantz, which was published just one year after.
* HeAlsoDid:
** Before creating the ''Gantz'' series, Hiroya Oku (the creator of the series) was the first voice of the Creator/OsamuTezuka character [[Manga/{{Unico}} Unico the Unicorn]] for the 1979 anime pilot ''Unico: Black Cloud And White Feather''.
** Rip Slyme, the group who provided the AnimeThemeSong, was also involved with the {{animutation}} "Foo-La-La".
* TheOtherDarrin:
** The CGI films have none of the actors return. In the dub, it’s recorded in Los Angeles rather than Texas, as ADV Films has long been shut down. [[note]]Noticeably, this wouldn’t have changed Masaru’s recasting, as Creator/IllichGuardiola’s [[RoleEndingMisdemeanor career has long been over]].[[/note]]

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