MAJOR SPOILERS AHEAD for the fifth episode of The Mandalorian Season 2, called "The Jedi."
The Mandalorian finally delivered something that many fans have been waiting a long time for in "The Jedi," with the live-action debut of none other than Ahsoka Tano. Mando sought her out so that she could take Baby Yoda and train him. While she did reveal his name is "Grogu" and that he was raised in the Jedi temple on Coruscant to be trained up until everything fell apart, she refused to train him due to his attachment to Mando. Instead, she directed Mando to take Baby Yoda to the planet Tython.
Unlike Tatooine and Nevarro that have already appeared throughout The Mandalorian so far, even diehard Star Wars fans who had their minds blown by "The Jedi" might not have recognized the name "Tython." Somewhat surprisingly, Tython has a history in both canon and the Legends continuity, and it's worth looking at what we know about the planet to consider what it could all mean for the future.
What We Know From The Mandalorian
When Mando attempted to hand Grogu over to Ahsoka (albeit somewhat reluctantly due to their connection) for training, Ahsoka refused, having already cited the dangers of training Force-sensitive people who have strong attachments. That said, she didn't leave Mando no better than how he started when he arrived on Corvus. Before she could head off to continue her Rebels quest to track down Thrawn (and presumably Ezra Bridger), she gave Mando a new mission:
There is one possibility. Go to the planet Tython. There you will find the ancient ruins of a temple that has a strong connection to the Force. Place Grogu on the seeing stone at the top of the mountain. … Then Grogu may choose his path. If he reaches out through the Force, there’s a chance a Jedi may sense his presence and come searching for him. Then again, there aren’t many Jedi left.
Ahsoka didn't describe what the planet is actually like, but Tython was clearly important to the Jedi before the Purge if there was a temple there. There are apparently mountains, if Mando will have to get to the top for the seeing stone for Baby Yoda. If Ahsoka is correct, Tython could be the parting place for Mando and his young charge.
What We Know From Current Canon
In the Star Wars canon that has existed since the reset, Tython was reintroduced as a planet in 2016 with a map for a Star Wars: The Force Awakens roleplaying game, then appeared a few years later in an issue of the Doctor Aphra comic book. Ahsoka wasn't kidding when she referred to the temple on Tython as "ancient," as it may have been the very first temple of the Jedi Order. Other candidates include Ahch-To, Coruscant, and Jedha. Even if Tython isn't the home of the first, the temple is indeed very old.
The main canon story set on Tython happens in the Doctor Aphra comic, during the original trilogy timeline. Aphra drew Darth Vader and agents of the Empire to Tython, and in the process kept them from discovering the rebel base and locating her loved ones. Things get a little weird when it comes to the "Martyrium of Frozen Tears," a confessional made of kyberite. It doesn't seem be what Ahsoka was referring to, but the confessional could have a part to play.
What We Know From Legends
A whole lot more about Tython was revealed in the Legends continuity that was removed from canon ahead of the premiere of the sequel trilogy, starting with The Force Awakens. Although the canon from the previous movies and Star Wars: The Clone Wars remained intact, all the Tython lore from its introduction in the 2007 novel Darth Bane: Rule of Two until the reset is no longer canon. That said, Star Wars TV has pulled from Legends before, with Thrawn (mentioned in "The Jedi") as a notable example from Star Wars Rebels. So, the Legends lore of Tython could become relevant again.
The beginning of Tython Legends lore goes all the way back to more than 35,000 years ahead of the original trilogy, and the environment itself was sensitive to disturbances in the Force, including the presence of anybody especially strong with the Force. Tens of thousands of years ago, the early Jedi (known as Je'daii) were torn apart by a civil war, appropriately called "the Force Wars." By about 1000 years ahead of the original trilogy, the previously verdant Tython was devastated and abandoned.
The planet was home to many species over the eons, with many cities and temples. The history of Tython is vast and expansive; while I for one am not expecting The Mandalorian to reintroduce the entire Legends history into canon, there may be some elements that are brought back when Mando and Baby Yoda pay the planet a visit. After all, The Mandalorian could have invented a new planet for the site of a Jedi temple. Perhaps using Tython means some of what was once canon is on the way back from Legends.
What It Could Mean
Well, for one thing, Mando and Baby Yoda journeying to a planet that was once important to the Jedi and presumably has a strong connection to the Force may mean that fans are getting even closer to having to see the duo go their separate ways, although that decision will seemingly be in Grogu's little hands. They could also wind up in serious trouble if they discover unfriendly Force-users on Tython. Mando had trouble holding his own opposite just Ahsoka; more than one might be too much, and Baby Yoda isn't exactly battle-ready.
Ahsoka sending Mando to Tython also feels like a shot in the dark, to me. The whole plan hinges on a miraculously surviving Jedi that "may" search for Gorgu, if such a Jedi even exists. Luke was likely busy elsewhere, after all. It would be fun if this leads to an appearance from Ezra Bridger, but my money isn't on it working at all.
Maybe it's the Rebels fan in me who watched the heroes flee from Inquisitors time and time again, but they could well wind up being chased by people who don't use the Force for good. Also, this mystical quest to Tython has me flashing back to the quest to Malachor on Rebels, and that's not necessarily a good thing. Whatever the case, we can only hope that The Mandalorian delivers some answers before the end of the second season. There is still the question of Moff Gideon's plans and how he'll use his dark stormtroopers, on top of everything Ahsoka piled on Mando.