Who We Have To Lose in Rebels
"Luke, when gone am I, the last of the Jedi will you be"- Yoda, ROTJ
This begs the question: do all the Jedi, including those in Rebels, have to die?
The simple answer is yes. Let's explore why.
When Luke is told by Yoda that he will be the last, it should be obvious that this does not mean he is the last force-sensitive individual in the galaxy. Just because you aren't trained doesn't mean you aren't a force user. So, does being force-sensitive make you a Jedi?
No.
Throughout the entire Star Wars universe, we get to see individuals who are force-sensitive and not trained. Some species or cultures forbid or frowned upon their children being trained in the temple. They looked at the Jedi like kidnappers who took children and never returned them. But once the children were grown, they did not call themselves Jedi even though they could use the force. Remember, Yoda says that Luke is the last, but even Leia was force-sensitive. Therefore, being force-sensitive does not make one a Jedi.
But Ezra was not trained as a Jedi in the temple and Ahsoka left the Order.
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I believe the above argument still stands. Ahsoka was a trained individual. Yoda knew she was alive because he saw her (and Ezra) in the temple on Lothal. He would not have forgotten about her. Yoda also communicated with Ezra in the same temple. Ezra was trained by a former Jedi and considered himself as such. Stating that none of the three must die is splitting extraordinarily tiny hairs.
So what did Yoda mean?
He meant that Luke was the last trained force-sensitive being in the galaxy. Although being trained did not technically make you a Jedi, (there were other trained, light-side using organizations out there) the general term was “Jedi”. If you were trained, the public, and emperor, would assume you were a Jedi. Being trained in this case seems to be the deciding factor.
When do they have to die?
Soon-ish.
In Rebels we are less that 2 BBY. That’s not much time. We know that Hera is alive during the battle of Yavin since we heard her name called over the loud speakers in Rogue. I am also of the opinion that Ahsoka is not dead yet and is helping the rebellion from the shadows. Her presumed death might be a fantastic opening for her to do some good. This is backed up by a quote from Dave Filoni “I’ve already been devising certain specifics around the future of the character. Where she is, what’s happening, how she survived if she did. All those questions I think they will need to be answered…” Ahsoka was Filoni’s baby. When she dies, it will be a moment to remember. That being said, I don’t know if we will see Kanan and Ezra die. The Rebels' series might stop 6 months BBY or so just so Disney doen’t have to kill off its new characters. It may also be that they were alive during ANH and died after the battle of Yavin, but I doubt that. We’ll have to see on that one.
The bottom line is, as much as it will pain me, our current Jedi must die. Otherwise, Yoda was wrong. Being force-sensitive does not make one a Jedi; being trained does. Therefore, anyone who is a trained, light-side user must not be alive by ROTJ.
I know. It sucks.