The final cutscene in Final Fantasy XIV: Endwalker’s 6.5 patch may have revealed one of the new classes set to be added to the game in the new expansion, Dawntrail. Beware, though; it’s pure spoilers from now on, so be careful before reading further.
According to some theories, a piece of three-leafed clover jewelry discovered by Krile in the final scene of the Endwalker’s 6.5 Main Story Quest indicated that Green Mage might be one of the new jobs added to FFXIV in Dawntrail. Keen-eyed sleuths on Reddit initially spotted the connection on the morning of Oct. 3, noting that a green three-leafed clover is the job symbol of the Green Mage in multiple other Final Fantasy games.

Could Green Mage be coming to FFXIV?
The Green Mage is a job that has primarily appeared in Final Fantasy Tactics games, which are based in the Ivalice universe. In both Final Fantasy Tactics A2: Grimoire of the Rift and Final Fantasy Tactics S, the Green Mage is symbolized by a three-leafed clover. Green Mages are also mentioned in Final Fantasy XII, another game set in Ivalice.
In those games, Green Mage is primarily a job for Viera. A defensive utility job, Green Magic allowed these Mages to use spells such as Protect, Leap, Blind, and Silence. They wielded hammers and maces and were primarily a support class.
This job will not be Veira exclusive in FFXIV. More likely, it will be the Viera who teach you the job. Additionally, in the crossover game War of the Visions: Final Fantasy Brave Exvius, FFXIV character Y’shtola can actually equip Green Mage as a secondary job, hinting that any race can wield the power of Green Magic.
However, there are also hints within the same cutscene that the Green Mage might have some help beyond a few protection spells. Speaking in the cutscene where the Green Mage symbol appears, Krile complains that her work is “so time-consuming, it would be nice for a Mammet to handle these tasks.” This could be a subtle hint that the Final Fantasy XI job Puppetmaster might also be included or be combined with the Green Mage.

In FFXI, the Puppetmaster saw players accompanied by a Mammet-like creature called an Automaton. The Automaton fought for by the player's side, while the player buffed it and attacked in hand-to-hand combat.
Overall, this is the strongest hint of one of the new jobs the community has had for Dawntrail. There were few definitive signs of a new job in the trailer, although some kind of pirate or corsair was theorized, partly due to Naoki "Yoshi-P" Yoshida's t-shirt hint during a recent keynote for Dawntrail. Given there are usually two classes an expansion, at the moment, Green Mage looks very likely.
Remember, though, treat all information with a pinch of salt until it's confirmed. After all, Square Enix has been teasing Geomancer for over three expansions now with no signs of a release.