I can't sleep, so:
What if?... My prediction/wishlist for the rest of Star Wars: Rebels Season 2 (Which I'm completely making up)
Alright, so Ahsoka states in this trailer that to defeat their enemy, Ezra and crew will have to get to know the way they think. To Ezra & Kanan (light Jedi) and Ahsoka (light/grey Jedi) this would mean that they'd have to learn about the dark side of the force. Of course, they can't just pick the next intergalactic bus to Vader's Star Destroyer to ask him about the Dark Side of the Force, as that would mean their certain doom. Instead of this, they turn to their only other option: history. Through some way (either the teachings of Ahsoka and lessons she learned in the gap between TCW and Rebels or some other unknown intel) they learn about the history of the conflicts between Jedi and Sith and with it the location of an ancient Sith academy somewhere in the Outer Rims where there are sure to be holocrons containing knowledge of the dark side.
The Jedi Trio, being Ahsoka, Kanan and Ezra, begin their search and are followed by Darth Vader and his inquisitors because he sure isn't going to let the loose ends that are Ahsoka and her pupils out of his eye. After a search through several systems they finally find the right planet and set foot on the planet we all know so well: Malachor V, location of the Great Scourge and the Sith Academy. They find the Academy and Ezra touches a pillar, which prompts the academy to awaken and open. Unbeknownst to them the inquisitors, who are scouting ahead, land on the planet and move to the entrance. There they find the trio about to enter the Academy and a fight ensues. After a lightsaber battle, the trio is able to enter the Academy, and close the door behind them. The trio is trapped inside and the inquisitors have to wait for Darth Vader to land. While they receive their master the trio is able to find a room in which they meditate on the nature of the force, maybe Ahsoka can explain her neutral/gray views. As soon as Vader and his companions enter the Academy the spirits of the Jedi who fell (who apparently all wore the same white uniform in the war) at the Scourge of Malachor arise and start attacking the evil they died fighting, Vader sets his inquisitors on them and continues to explore the temple by himself, alone. The trio flees but lose each other because of all the commotion, from now on they will have to find their own way through the temple. So now we have the three main force-sensitive characters in Rebels and a frikkin' Sith Lord on themselves in an ancient Sith Academy. I think it would be cool if they all take something different away from the experience. Perhaps they all learn something about their respective side (Kanan: light, Ahsoka: grey, Ezra: dark) After exploring for a while Kanan has a vision of an ancient Jedi (a certain general maybe?) which takes place in an ancient jedi training room. He explains to Kanan the history of the Jedi and the way of the light side. Besides this he states that he can feel the pull the dark side has on Kanan's apprentice and warns him. After this warning he summons two other jedi and throws Kanan an extra (red?) lightsaber, the four of them spar with the goal of training Kanan and letting him prove his worth as a jedi.
Meanwhile Ahsoka is on her own exploring the temple as well. She comes to a meditation room and falls to her knees when she suddenly hears the voice of someone she hasn't heard of in a long time: Anakin Skywalker, her former master. This can either be the Sith Academy playing with her mind, or the thoughts of the real Darth Vader reaching her as he's exploring the temple in solitude as well. She contemplates the differences between herself and her master and the dark and light side and continues her journey to the center of the Academy, where the Holocrons lie.
At the same time Ezra is on himself exploring another side of the temple, and he comes to a place where he finds a lightsaber half buried in the sand. He switches it on and it turns out to be an ancient lightsaber last used during Old Republic, so the design is ancient. Whose lightsaber it is is anyone's guess. It could be Darth Revan's, the Exile's, random Joe Schmoe's etc. If you really want to have some fun you could say that this is the lightsaber that Kylo Ren will base his lightsaber design on. Moving along, Ezra feels the pull of something powerful more and more, after following it he comes to a giant chamber containing holocrons filled with ancient Sith knowledge, the reason they came to the planet in the first place. Just as he moves to pick up one of the holocrons he hears a voice behind him and turns around to see a cloaked figure in the room, the one Sith lord that the Star Wars saga kind of forgot: Darth Maul. After the ending of the Clone Wars, Maul went on the run to the Academy he learned about in his teachings from Palpetine: the ancient Sith academy on Malachor. He recognizes a need for knowledge of the dark side in Ezra and he offers to teach him about it, as he has been studying them for more than a decade. This is actually a pretty brilliant move of the makers of the series (if they do this, that is) because it accomplishes two things: - It fixes the loose threads left hanging after the cancellation of TCW containing the resurrection of Maul with no catharsis in the end.
- It gives Ezra a teacher who knows a lot about the dark side but has no stake in turning him to Vader or the Empire.
Kanan, Ahsoka, Vader and the Inquisitors arrive at the central hall as well and from there on the script contains a lot of "They fight." (To quote George Lucas in the making of Ep. III). The season ends with Ezra being Maul's new apprentice and on his way to the dark side, Vader recognizing the danger of another Sith Lord opponent, Ahsoka and Kanan being on a quest to save Ezra and redeem him. Ahsoka already saw her master turning and knows that it is a one-way street. Kanan doesn't want to see his teachings fail his student, mirroring how Obi-Wan felt his teachings failed Anakin. And on that note we begin the excruciating wait to Season 3.