Had the 2011 Green Lantern movie starring Ryan Reynolds been a part of the DCEU, the franchise would have looked very different today. In 2011, with the superhero genre going from strength to strength during the early stages of the MCU, DC was ironing out plans for a franchise of their own. Early on, this included the idea to incorporate Christopher Nolan's Dark Knight trilogy into what became the DCEU, but there was also another movie that could have served as the first film in the franchise had things worked out differently.
After spending 14 years in development hell,Green Lantern introduced Ryan Reynolds' version of the titular hero to a live-action format. Following the story of Reynolds' Hal Jordan, as he assumes the mantle of Green Lantern, the film made a valiant attempt at capturing the basic essence of the character while still appealing to a wide audience. However, Green Lantern was widely criticized upon release for its writing, poor CGI, and overly comedic tone. As a result, Green Lantern was swiftly swept under the rug, and plans for future DC movies moved on without it.
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Had things worked out slightly differently, however, Green Lantern could theoretically have served as the beginning of the DCEU. Despite its shortcomings, Green Lantern had more than a few traits that would have proven beneficial to the DCEU, whose problems have been substantial and well-documented. In addition, the DCEU could have retroactively addressed some of the issues with Green Lantern, making Reynolds' hero an integral part of the franchise's world in the process.
One of the most criticized aspects of the DCEU (as it stands) is its tone is often needlessly gritty.
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