Summary
Scrapped concept art fromArrowrevealed an unused Green Lantern suit for John Diggle, which featured Diggle holding a gun - a detail that received a divided response from audiences. DespiteArrowrunning for 8 seasons and heavily implying that John Diggle would eventually become the Green Lantern ofthe Arrowverse timeline, the storyline never truly came to fruition.
11 Years Ago, DC Proved A Green Lantern Show Is Better Than A Movie
Green Lantern: The Animated Series proved that a show works better than a movie for the character, making the upcoming Lanterns an exciting project.
Why Arrow’s Green Lantern Design Reveal Divided Audiences
The biggest point of contention about John Diggle’s revealed Green Lantern suit is the presence of a gun. The power of the Green Lanterns is the ability to create anything they can think of, so it might not necessarily make sense for John Diggle’s Lantern to carry another weapon which such a useful tool at the ready. This oddly fits within the Arrowverse, though, which has more-often-than-not gone with a more practical approach to the power sets of a lot of its superpowered beings.
Of course, John Diggle never actually became the Green Lantern throughout the entirety of the Arrowverse, despite having multiple teases over the years.The Arrowverse was limited to what heroes it could and couldn’t use, which could be one of the reasons why the Green Lantern story never had a full conclusive run. Even though John Diggle never wore a proper Green Lantern outfit in the show, it was fun for fans to know that he essentially would become one at some point, though the inclusion of his gun might have turned some fans off if he ever did appear.

The Arrow Green Lantern Complaints Ignore The Comics' Own Lore
If John Diggle ever had become the full official Green Lantern of the Arrowverse, drawing inspiration from Simon Baz’s storyline and justifying his guns in this manner could have worked effectively.
These complaints ignore an interesting aspect of the more modern lore of Green Lantern and the introduction of another Earth-based Lantern, Simon Baz, back in 2012. When Simon Baz was first introduced, his newly acquired ring failed him and left him defenseless.After that incident, Baz decided to carry a gun for self-defense just in case his lantern ring ever failed again, providing an interesting aspect to his story.

There have been countless moments throughout the Green Lantern Corps' history when a member of the Corps has found themselves at the mercy of their own ring that does not have an infinite amount of power and has failed as a result of being drained. As such, if John Diggle ever had become the full official Green Lantern of the Arrowverse, drawing inspiration from Simon Baz’s storyline and justifying his guns in this manner could have worked effectively.
It would have been fun for fans ofArrowto finally see all the Green Lantern teases properly pay off for John Diggle, but it unfortunately never came to be. The Green Lantern concept art for Diggle shows what direction the creators could have taken with the character, making him much more grounded than what a hero like Green Lantern typically is shown to be. However, arguments surrounding various aspects of the Arrowverse have been going on since its inception, and the potential Green Lantern gun controversy is just one more thing fans could have been divided about.

Arrow
Cast
Arrow is a television series that debuted in 2012, featuring Stephen Amell as Oliver Queen, a billionaire playboy who returns to Starling City after being stranded for five years. Transformed by his experience, Queen becomes a vigilante archer, aiming to purge his city of crime and corruption.