Ahsoka creator and writer Dave Filoni, who will also be directing his own culminating feature film for the MandoVerse, even stated that Thrawn was "definitely" the main villain of the New Republic era.
This immediately caused fans to speculate that he would in fact be the main antagonist of Filoni's upcoming movie, and the finale of Ahsoka only fueled that theory.
How Did Ahsoka Set Up the MandoVerse Movie?
Warning - The rest of this article contains spoilers for Episode 8 of Ahsoka.
Season 1 of Ahsoka ended with Grand Admiral Thrawn escaping Peridea and returning to the Star Wars galaxy.
He took the Great Mothers of Dathomir with him on this journey, and the last viewers saw, he was actually heading to the witches' home planet with a cargo hold full of caskets that likely contained dead stormtroopers.
This brief scene indicates that Thrawn will continue his alliance with the Great Mothers in the near future and will help and protect them in exchange for their services.
It is possible that Dathomir will not only be the location where the Great Mothers will reside as they help Thrawn but also the location that Thrawn himself will use as a home base, so to speak, as he rebuilds the Empire.
Once the New Republic gets word that Thrawn is back and is in leagues with the Great Mothers, they will likely want to act quickly to squash them before things get out of hand.
However, that will be easier said than done because Thrawn already planned out his coming reign of terror.
Because of his alliance with the Great Mothers, Thrawn wouldn't have to worry about recruiting an army to aid the Empire. He already has hundreds, if not thousands of stormtroopers that can be resurrected by the Great Mothers into Night Troopers, so in a certain sense he is in possession of an unlimited army.
Interestingly this briefly lines up with Thrawn's plan in the 1990's Heir to the Empire book trilogy that Filoni is taking inspiration from. However, instead of using the Nightsisters or Great Mothers to fuel his army, he instead used cloning technology on Mount Tantiss.
Having an unlimited supply of ground forces will undoubtedly give Thrawn the upper hand in the coming war, but they still wouldn't be a match for powerful Force users such as a group of Jedi.
That is where the Great Mothers themselves come into play.
Just as Morgan Elsbeth was able to fight off Ahsoka Tano in the Season 1 finale with the Blade of Talzin, the Great Mothers can conjure up other magickal weapons to use against Force wielders.
As seen in Star Wars: The Clone Wars, they can also use their magick to actually physically enhance certain people just as Mother Talzin did with Savage Opress.
Therefore, it is obvious that Thrawn's decision to ally himself with the Great Mothers was extremely calculated, and it is a decision that, on paper, seems like it will pay off. With that being said, the New Republic and any Jedi that join the fight will have a difficult task in front of them, so how will they eventually win?
How Will Thrawn Be Defeated?
Grand Admiral Thrawn did not appear in any of the sequel trilogy films, so he will have to be defeated at some point in the timeline between the end of Ahsoka Season 1 and the start of The Force Awakens.
However, since he is in possession of so much power, how will he actually be defeated?
The key to everything is now the Great Mothers and Dathomir. Once they return to their home planet and get everything they need set back up, it will be protected by Thrawn and the rest of the Empire at all costs.
Since the Great Mothers can continuously give Thrawn an army, someone will have to try to sneak past the Imperial defenses and actually travel to Dathomir, kill the Great Mothers, and then Thrawn will be on his heels.
Perhaps the group of MandoVerse characters like Din Djarin, Grogu, Bo-Katan Kryze, Cobb Vanth, Boba Fett, and Luke Skywalker can go on this mission together just as Jyn Erso and Cassian Andor's band of characters infiltrated the Imperial base on Scarif in Rogue One.
As previously mentioned, defeating the Great Mothers won't be an easy task, but it also won't be impossible.
All of the convolved characters will have to do their own part to ensure success, but it will likely be a Force user such as Luke or Grogu that ultimately defeats the witches since they are so powerful.
After they are ultimately killed, though, the New Republic forces will either have to destroy or capture Thrawn and the rest of his forces either in a space battle or a ground siege, depending on where he decides to fall back to.
The Grand Admiral will likely still have a few tricks up his sleeve, but the New Republic will obviously be able to emerge victorious in the end.