'Crisis on Infinite Earths' uses Green Lantern Corps from Ryan Reynolds' 2011 film to tie them to the Arrowverse
This article contains spoilers for 'Crisis on Infinite Earths' Part 5
Green Lantern fans have been dying to see the hero make an appearance in the Arrowverse for a very long time. So obviously, The CW decided to oblige them during the 'Crisis on Infinite Earths' Part 5.
Long story short, the Arrowverse just combined in the same storyline as shown in the 12-part comic. The episode opens with the worlds merged and the superheroes all stuck on one Earth but the crossover deviates from the comic by introducing a full multiverse at the end of the episode.
One of the worlds we see features the Green Lantern Corps, reusing footage from Ryan Reynolds's disastrous 2011 movie. This means the film is officially a part of the Arrowverse but don't expect Reynolds to start making cameos in the green suit anytime soon.
The 'Deadpool' star has made no secret of his disappointment with the movie and he's taken shots at it in multiple interviews and even in a scene from 'Deadpool', his much more successful superhero movie.
However, fans of the character can still hold on to some hope as a 'Green Lantern' TV show is reportedly in the works for HBO Max.
'Crisis' had a number of references to the Lanterns, with the Monitor (LaMonica Garrett) revealed to be from the planet Maltus, the homeworld of the little blue aliens known as the Guardians of the Universe who are essentially the Lantern Corps' bosses.
Plus, the Monitor's origins, as revealed in Part 4, closely mirror the story of Krona, a rogue Guardian from the comics.
Despite all the references and the reused footage, 'Crisis' didn't include a cameo by a Green Lantern and seeing as the Lanterns are situated in a different universe, they're unlikely to make an appearance on any of the Arrowverse shows.
This is the closest we've ever come to getting a sequel to 'Green Lantern' and perhaps that's for the best.