Also unintentional, but Saxon (voiced by Ray Stevenson, who is Northern Irish-English) growling Rau's last name sometimes just sounds like a regular growl of frustration, or in some cases, "rawwwwwwr..." Like the Zeb example above, it's strangely fun to hear and mimic.
Ray Stevenson unintentionally did this to himself, as he was flying in from filming Black Sails when he came in to record for "Legacy of Mandalore" and had no time to read the script, so he didn't know until he got to Lucasfilm that Saxon would get killed.
The epilogue to "Family Reunion and Farewell" was kept very closely guarded with only a handful of cast and crew knowing what happened (Kevin Kiner, the composer, even mentioned he was sent the episode with the last two minutes missing), with most of the cast only finding out what happened to their characters when it aired. Namely, Vanessa Marshall had no idea Hera was pregnant during the final few episodes, while Taylor Gray recorded Ezra's sacrifice not knowing he would survive it.
Vanessa Marshallrevealed in an interview how she didn't know she auditioned for Hera in this series. She was given a general description of the character, but nothing specific, including the fact that this was for a Star Wars series.
Possibly unintentional, as his role in Rebels is more of a shoutout to the Battlefront games if anything else. Corey Burton voices a character who is a drill sergeant to military cadets, but unknown to him, at least one of them is a rebel spy (and at least another would become a turncoat). In Transformers Animated, he is the spy, and the guy he framed becomes a genuine turncoat.
Actor-Shared Background: Kind of. Sabine is voiced by Tiya Sircar, who is Indian. When her family is introduced, Ursa is voiced by Sharmila Devar, while Tristan is voiced by Ritesh Rajan, who are also both Indian. Alrich, on the other hand, is voiced by Cary-Hiroyuki Tagawa, who is Japanese.
And then Celebration 2017 showed Rex will don the same garb as the old soldier later in Season 4.
And then the show's epilogue all but confirmed it by revealing that Rex did fight at Endor, although technically it hasn't been officially confirmed that he and the old soldier on Han's team are one and the same.
Awesome, Dear Boy: An interview by Filoni post-Season 2 finale revealed that tons of people (including actors) have and are still going up to him to audition for Rebels to join Star Wars, and many of them are making it in. This combined with So My Kids Can Watch are the top motivators for most of the voice actors. (For example, Philip Anthony-Rodriguez auditioned for The Clone Wars before, Kevin McKidd has always wanted to at least play a Stormtrooper, and so on.)
The leader of the Ghost rebel crew, Hera Syndulla, is voiced by Vanessa Marshall. Marshall's ex-husband, Andrew Kishino, played the Partisan rebel leader, Saw Gerrera, back in The Clone Wars (though Forest Whitaker plays Saw here like he did in Rogue One).
Kevin McKidd was the main character of the short-lived Journeyman television series. Here, he's the leader of the Journeyman Protectors.
Kallus's first name being Alexsandr is a reference to a production manager, Alex Spotswood, who voices him in temp recording.
Andrew Kishino, the original voice for Saw, plays a minor character in Rebels that is nearly the exact opposite of Saw's current characterization—a Reasonable Authority Figure Imperial trooper that puts the well-being of the innocent first.
He also uses a similar inflection he uses for Janja in The Lion Guard, a Mook Lieutenant that worries about his own skin but wants to look good in front of his superiors—which is the characterization of Captain Hark's boss, Tiber Saxon.
Warwick Davis has a long history of physically playing but not voicing various aliens throughout the franchise. Now he's playing a character only through his voice.
In regards to the franchise in general, Andi and Hidalgo have tweeted their disdain for shipping. As for the show itself, Steve Blum was informed on Twitter of Tumblr's fondness for Kalluzeb and didn't seem particularly enthused by it when he found out (Freddie, on the other hand, made a light-hearted joke about it)... and then they started poking fun at it at Celebration 2017 and Steve even teased the Kalluzeb shippers on May the Fourth 2017.
Tiya Sircar gently put down the idea of Sabezra happening (also debunking that it would happen) at Celebration 2016.
Chopper was made into a real robot (that is totally not remote-controlled, possibly) that they use for promotional events and materials. Since then, he's been wandering Lucasfilm Studios, made guest appearances in some TV shows, and was used for a cameo in Rogue One.
R3-A3 has also been brought to real life, though it's not clear if just a statue of him was made or it's a robot/RC like Chopper.
A relatively benign example, but Taylor Gray, the voice of Ezra started off with minimal familiarity with the Star Wars franchise. The writers and producers discouraged him from doing any heavy "research", so that his reactions to lore would be more genuine. He's also the youngest of the group and the only one who hadn't voice acted before, giving further weight to his role as a newcomer.
Cast interviews also indicate that Freddie Prinze Jr., the voice of Kanan, was the one that mentored him in voice acting. It took a while for him to catch on, but he once he did he liked the idea since it mirrored their characters' relationship.
On the other hand, voice actors of major characters who did not watch The Clone Wars were advised to watch the relevant arcs so to gain a better understanding of what their characters had gone through. In one case, Tiya Sircar, the voice of Sabine, was told to watch the entirety of the Mandalore arc.
During the recording for "Jedi Night", the voice actors were given the script missing the last two pages and recorded it as normal, and only saw the storyboard for Kanan's death scene moments before they recorded it to make their reactions more genuine.
Executive Meddling: Not quite, but the midseason trailer of Season 2 showed a lot more than what Filoni wanted, due to a large number of spoilers being revealed in it. The editing for the midseason trailer of Season 3 ended up being supervised by Filoni, with Word of God saying that a lot more spoilers were kept out of the trailer than one may assume.
Though its for a term, "Ashla-touched" being the Lasat term for "Force-sensitive", especially regarding those who are Lasat themselves.
The Grand Inquisitor was affectionately called "Inky" and "Quizzy" by some fans.
The Ghost crew being aspace family. Hera and Kanan are near-universally "Space Mom" and "Space Dad", but it's not uncommon to see similar titles with the other members of the crew. Ezra, for instance, is often called "Space Aladdin".
The main protagonists are sometimes called the "Big Jedi 6" due to them being somewhat similar to the main protagonists from Big Hero 6.
Ezra has also been referred to as "the Blueberry" in reference to his blue eyes/hair. "Blackberry" for in case he goes Dark Side.
Fans started referring to the Seventh Sister as Buffy the Jedi Slayer after Sarah Michelle Gellar was revealed to be her voice actress. Before her name was revealed, she was commonly referred to as "The Femquisitor", or the more snazzy "Femquizzy".
The Fifth Brother is known as "Clyde" on Tumblr, following how the Grand Inquisitor was called "Inky" for short, as a reference to the names of the Pac-Man ghosts.
"Jetstream Sam" is also popular since he shares the voice actor with the Metal Gear Solid character.
To a lesser extent, the Seventh Sister has been called "Bonnie", as in Bonnie Clyde.
Some fans refer to Sabine as "Bean", or "Raspberry" to a lesser extent, to go with Ezra's nickname "Blueberry".
Though it's canonically used by his family, Zare is sometimes called "Zare Bear".
Ahsoka has been nicknamed "Space Aunt", and Rex "Grunkle/Grandpa Rex" to go with the whole Space Family concept. Cham has also been referred to as "Space Grandpa" as well.
Whenever it seems like someone is about to join the crew, they get a nickname to follow the motif too. For example, Kallus (should he go down the redemption arc path) would be the Space Uncle, Azadi is another Space Grandpa, so is Hondo, and so forth.
When the first Season 3 trailer revealed that there was another Fulcrum, people started calling them Fulcrum II/2.0 before their identity was revealed. Post-reveal, people just call them by their real name or sometimes their codename side-by-side (Kallus/Fulcrum) like with Ahsoka (who was no longer a mystery) and Cassian (who was never a spoiler identity due to him being a Fulcrum not being plot-relevant to Rogue One and being openly stated as one in All There in the Manual).
The incident on Lasan being called "the Cleansing of Lasan" or the lesser used "the Massacre of Lasan", though Legends called it the Apprehension of Lasan and canon calls it the Siege of Lasan. An official article about The Roleplaying Game from Fantasy Flight Games even refers to it as the Cleansing of Lasan.
For Jacen in the series finale, his nickname is either Broccoli Boy or Asparagus Boy due to his green hair and being the son of two characters associated with the color green.
Fandom Nod: At Celebration 2017, the Rebels main cast and Filoni poked fun at #HotKallus (most of what they know having originated from the show's staff themselves) and the fandom's sudden fondness of Kallus in light of his HeelFace Turn and his rather appealing loose hair lock, which then led to Steve Blum, Dave Filoni, and the host joking about how Kallus/Zeb is the ultimate bromance and that Zeb would settle down on Lirasan with Kallus & have kids with him. Needless to say, it was rather surreal for the fandom on Tumblr.
God Never Said That: Many people were under the assumption that the show was going to last all the way to season five, six, or seven, due to a comment by Freddie Prinze Jr., who actually stated that it was within the realm of possibility that the show could last that long, not that it would. In addition, about the same group of people also believe that the show would depict the events of Rogue One and the Battle of Jakku from the Ghost crew's perspective, due to Filoni expressing interest in doing so, which again, was not something set in stone when he said that. And then Filoni announced at Celebration 2017 that the show would end at Season 4, just out of arm's length of the Battle of Scarif and a great distance away from the Battle of Jakku. Though if you wanted to be technical, the epilogue takes place "after the war".
People figured out that the Seventh Sister was a Mirialan based on her appearance in a bit of concept art that showed her green skin. Unlike most examples, however, it was part of a larger fan-speculation that did not come to pass, as most were betting on her being Barriss Offee, a fallen Mirialan Jedi and former friend of Ahsoka whose last known fate was being imprisoned under Republic custody in Star Wars: The Clone Wars. After "The Future of the Force" aired, the possibility of that falls close to none as the Seventh Sister was completely out of her league against Ahsokanote Whereas Barriss was able to beat her in combat through skill and trickery. and neither acknowledge any recognition beyond hunter and hunted.
A single piece of info from All There in the Manual said that Sabine inherited her Nite Owl helmet, leading to support the theory that Sabine's mother or another female relative was ex-Death Watch. Also somewhat supported by her neutral comments on Death Watch in her journal. Come "The Protector of Concord Dawn", Sabine reveals her mother used to be Death Watch.
Some people suspected that Kallus was lying about giving the order to deploy disruptors on Lasan, due to the Fridge Logic of having an espionage agent making a big decision that should belong to a more superior power such as a general, as well as a a mysterious lack of information from his POV in the "Droids in Distress" novelization (as in, it never says anything like "He remembers how he gave out the deployment of disruptors", and instead says things like "The Lasat should've died a long time ago, and it was time to fix that fact."). It gets proven true in "The Honorable Ones", where he admits that it wasn't supposed to be a massacre, suggesting that he was ordered by someone else to use the disruptors.
When Word of God revealed that the Grand Inquisitor had shown up in The Clone Wars, one theory was that he was a former guardian of the Jedi Temple, since they always kept their faces covered and wielded double bladed lightsabers. Come "Shroud of Darkness" and one of the Temple Guards in Kanan's vision reveals himself as the Grand Inquisitor. Later on, Dave Filoni confirmed that he was indeed once a Temple Guard, specifically one of the guards who arrested first Ahsoka and then Barriss Offee, and was filled with doubt after Barriss' proclamation that the Jedi had been corrupted.
Another common theory was that the Dark Side planet seen in the final Season 2 trailer was Malachor (based on the planet's general appearance, and being alluded to in supplementary material for The Force Awakens as the place where the design of the crossguard lightsaber originated). Come "Shroud of Darkness", it's made clear that Malachor is this very destination.
The Fifth Brother's Animal Eyes looking similar to cataracts and the show's emphasis on his skill with the Force (especially sensing others) caused people to believe he was blind. An interview with his voice actor revealed that his work-in-progress name besides the "Male Inquisitor" was, in fact, the "Blind Inquisitor".
Quite a few people guessed that Ezra's new lightsaber would be green before it was confirmed. Supported by when Filoni tweeted a photo with an angled green laser behind Rex back on May the Fourth, prior to Celebration 2016.
When Filoni tweeted another photo of an unknown dark green object with jaig eyes, one of the guesses was that it was Kanan's mask. This ended up being the case.
Shortly after being cancelled, Disney Infinity revealed on its YouTube channel that Hera (whose figure had been conspicuously missing from the crew line-up) would've been released later on in 3.0's life. Some noticed that Hera had a different torso from her current appearance in the show (around the time Season 2 ended), leading to guesses that this was her Season 3 appearance. This ended up being correct, and this also suggests that her figure would have been released towards the end of 2016.
Long before the release of the third season trailer, articles had discussed rumors of Thrawn's immigration to the EU canon on Rebels.
People felt like Sabine would get a jetpack, considering it would be jarring if she was the only Mandalorian warrior without one. Gets lampshaded towards the end of Season 2, before it turns out she gets a jetpack in Season 3.
Considering everything she had been through and The Reveal that she was of House Vizsla, it was guessed that Sabine would be the next holder of the Darksaber at some point, and this would have something to do with Maul/the Mandalorian Myth Arc due to its fate being undisclosed. Come Season 3, and she is the new owner of the Darksaber, with Word of God saying that it will end up being a plot point for Sabine and the Mandalorians.
People immediately called the new Fulcrum being Agent Kallus who has committed a HeelFace Turn once a new Fulcrum was revealed and Kallus was suspiciously absent in the Season 3 trailer. Building up to The Reveal in "An Inside Man", people not only found Fulcrum's voice familiar, but Kallus' behavior also raised some eyebrows (such as helping the pilots defect and showing discomfort with Thrawn's modus operandi).
Many had speculated that one of Maul's goals following his escape from Malachor would be to seek out (and kill) Obi-Wan Kenobi. In "The Holocrons of Fate", this is heavily implied to be the case, and it's outright confirmed in "Visions and Voices".
For Rogue One, through Epileptic Trees, people assumed that Chopper was sent over to England to be cast in the film rather than for Celebration (where he was absent). He makes a cameo appearance in the background.
Also, ever since Rogue One was announced, people also guessed that the Ghost would get a cameo appearance as a Freeze-Frame Bonus in the Rebel fleet, and that the most likely member to be at least mentioned being present would be Hera. With Chopper being present, a "General Syndulla" being mentioned (confirmed to be Hera), and an unnamed VCX-100 (also later confirmed to be the Ghost) among the fleet, they got it on the money.
Some assumed that there were more Fulcrums or rebel informants with codenames than just Ahsoka, which was confirmed in Season 3. People also then came to guess that Cassian Andor from Rogue One was a Fulcrum, due to being a recruiter and a member of Alliance Intelligence, which would then be confirmed in All There in the Manual.
It was guessed that the Imperial supercommando accompanying Sabine's clan was Sabine's older brother, once it was revealed that Sabine has a living brother.
For non-Rook Kast theorists, some of them guessed that Sabine's last name was actually inherited from her mother.
When Sabine got a hold of the Darksaber and began her training in "Trials of the Darksaber", some complained that she had no claim and leadership over it because she did not formally kill Maul, the last holder of the weapon, in order to receive it and instead looted it from his stuff. This was actually addressed in the next episode, "Legacy of Mandalore", where another character points out this exact problem, with the new holder pointing out that this is as good as it gets (because Maul has no interest in Mandalorian affairs anymore and there is no way she'll be able to defeat him), affirming later that she doesn't intend to becoming a permanent leader of Mandalore and instead wants to reform Mandalorian culture so that it can be more universally beneficial.
People guessed that due to a lack of mention in post-Rebels works, the Mandalorians either stay independent from the Rebellion, have a minor role in the Rebellion, or a Mandalorian uprising fails, with the first two possibilities being what happened with the Free Ryloth Movement earlier on in the show and as we learn later in Bloodline. In the ending of "Legacy of Mandalore", a character says that the Mandalorian Resistance will rise on its own, independent from the main Rebellion, at least for now.
Starting all the way back from pre-release information that Kallus is an Imperial Security Bureau officer, many immediately guessed that Yularen (who is involved in the Imperial agencies) would make an appearance in regards to Kallus's job. A connection between the two was confirmed in All There in the Manual before Yularen himself debuted in "Through Imperial Eyes". It was also correctly assumed that Yularen had a good memory of Kallus and that Kallus looked up to Yularen, but it was Jossed that the two interacted on a regular basis and a bit beyond just a superior-subordinate relationship, as the episode revealed that Yularen only remembers Kallus as a star pupil at the Royal Academy and that Kallus does indeed idolize Yularen. However, it did also confirm that Yularen would be disappointed in Kallus for being Fulcrum.
When Lyste was shown to be involved in "Through Imperial Eyes" as being alongside Kallus, it was guessed that Kallus was going to frame Lyste as being Fulcrum.
The masked bounty hunter from the second Season 3 trailer being a disguised Ezra sent to help retrieve Kallus in that episode as well, people being tipped off by Sabine's stylized design of a lothcat on his helmet and the same boots that Ezra has. Funnily enough, even though Thrawn never got to see Ezra in this disguise in the episode, he deduced in-universe that it was Ezra by the former reasoning listed here.
Obi-Wan's line from the Season 3 midseason trailer, "You're in the wrong place", actually being directed to Ezra as a part of their meeting and not a Pre-Asskicking One-Liner to Maul.
The Cavalry in the summaries for "ZeroHour" was guessed to be either the Bendu and/or Clan Wren. It is indeed both.
Sato and Konstantine dying by the end of Season 3, likely having something to do with each other in regards to Thrawn.
Kallus surviving Season 3 to join the Rebellion.
A minor one, but fan artists were fond of messing up Kallus' hair (with pseudo-bangs), often in the context of being in a fight. He gets beat up in "Zero Hour" by Thrawn, and his hair gets tussled similarly to how fan artists depicted.
There was actually an instance on Tumblr where a couple of users were trying to figure out the musical cues of the characters, with someone guessing that the cue in "Art Attack" after Sabine escapes her explosion was her cue. Cut to about year later, and they were right.
Rau and Bo-Katan having met in the past since the former is essentially the leader of the Mandalorian royal guard while Bo-Katan is a Fallen Princess, as well as that the two were active during the Clone Wars. While it isn't explicitly confirmed, the two have moments that imply they've worked together before in the past. It was also guessed that the two's personalities would be Red Oni, Blue Oni until it becomes a fire-forged friendship/Back-to-Back Badasses, which is only implied or briefly shown.
Kanan dying in the second half of Season 4 (which, had been theorized for every season in the show, so it had to be true at some point), which is related to...
Kanan is the wolf in the Season 4B trailer, due to sharing a similar facial structure (including blue eyes) and being friendly to Ezra.
The fate of Ezra and Thrawn at the end of the show being that they went MIA and are somewhere else in the Galaxy.
Sabine being involved in Ezra's fate at the end of the show.
Given the events of "A World Between Worlds", Ahsoka showing up at the end of the finale to look for Ezra.
Hera being pregnant with Kanan's child at some point during the show, with the epilogue showing that she's taking care of their baby.
Thrawn's fate having to do with literal tentacles, as the Bendu prophesied at the end of "Zero Hour" that his defeat involved him being "surrounded by many arms in a cold embrace."
The Latin American Spanish dub was dubbed with both Mexican and Argentinian voice actors, when normally each country dubs their own titles separately. Since the films and previous series were dubbed in Mexico, most of the cast, including returning characters, are dubbed by Mexicans, when the Argentinian voice cast dubs many of the new characters.
The European French dub uses mostly Belgian actors, while the returning Star Wars characters have their lines recorded in Paris with French actors.
Irony as She Is Cast: Vanessa Marshall is fluent in French, yet Hera is the only Twi'lek we've seen that does not have a French accent. "Homecoming" establishes that she once did have a French accent, as evidenced by a brief Accent Relapse.
The Rebels Recon post-episode online segments often includes Pablo Hidalgo telling people their fan theories (particularly the ones involving the incorporation of Legends canon) are either false or only true in the most barest of superficiality.
In "Legacy of Mandalore", we learn that Sabine's mother is an original character named Ursa Wren and not Rook Kast, as was popularly speculated to be the case.
Hidalgo has strongly opposed the strangely popular theory that Kallus is/becomes Madine, which, when coming from Hidalgo, it pretty much means that no, Kallus and Madine definitely are not the same person. Gilroy also sarcastically said that it's an "interesting theory".
Dave Filoni has made it pretty clear that no, the wolf in the season 4 trailer is not Ahsoka.
In the "Rebels Recon", Filoni clarified that Kanan's death was because that was where his story went and where he needed to go for the rest of the crew, as an example of selflessness and sacrifice, not because he was Doomed by Canon or because he "had to die".
While Filoni approved of the "Rex was the old bearded guy" at Endor initially, he eventually changed his mind and Nik Sant and Rex were stated to be two different characters.
Season 1 of Rebels premiered October 3, 2014, exactly six years after the Season 1 premiere of The Clone Wars.
Season 1 ended on March 2nd, two years (And only five days off) after the Season 5 finale of The Clone Wars (March 7th). The Season 5 finale of The Clone Wars ended with Ahsoka leaving the Order, and the Season 1 finale of Rebels ends with the reveal that Ahsoka is Fulcrum.
Lying Creator: Prior to the release of the trailer for the second half of the fourth season, several of the people involved with the show denied that Emperor Palpatine would be making an actual appearance beyond his audio-only cameo in the Season 2 premiere.
When "Steps Into Shadow" premiered, the Star Wars Twitter account started making comments about how Ezra is Blueberry no more and put up a poll about his newhairdo, with the 'against' option being called "Bring back the Blueberry!"
In light of fans finding Kallus's "rebellious" lock of hair (similar to Obi-Wan's single lock of hair from the final Mandalorian arc in The Clone Wars) and other predicaments in "Zero Hour" rather attractive — specifically, the growing Twitter tag, #HotKallus, Filoni revealed in a podcast that he was quite aware of it because the name of that meme came from within the team (mostly likely Lucasfilm publicist, Tracy Cannobbio, judging by her tweets). Just about the entire main cast has gotten in on it, and even David Oyelowo is aware of it (according to Filoni, he thinks everyone is crazy and he agrees).
In a commercial promo for "Twilight ofthe Apprentice", Ahsoka asks Maul what game is he playing. In the show, he basically affirms that this is an Enemy Mine, while in the commercial, he says, "The endgame, of course."
In the Season 3 trailers, The Reveal/Wham Shot scene where Thrawn is shown walking out of the shadows in his office on the Chimaera, which was said by Word of God to be from a later episode in Season 3. It does not appear. Likewise, he also says "We will show the Galaxy what happens to those that dare speak against the Emperor", which presumably applies to either "Secret Cargo" in regards to Senator Mothma, or "ZeroHour".
In the Japanese dub Yohei Tadano (Gen) replaces the late Ichirō Nagai as the official voice for the same character. The same goes for Darth Vader, since he was voiced by Toru Ohira, who is normally the regular dub voice of Vader in Japanese in the films in the first season and after his death he's replaced with Taiten Kusunoki from season two onwards.
A somewhat complicated example: Sam Witwer voices Palpatine, replacing Tim Curry from the final two seasons of The Clone Wars, who himself was a replacement for the late Ian Abercrombie, who was filling in for Ian McDiarmid from the films. Also counts as Role Reprise, as Witwer voiced Palpatine in the Force Unleashed series. Then by the fourth season, Ian McDiarmid reprises his role as the Emperor/ Darth Sidious for a definite scenery chewing act.
In the Latin American Spanish dub, Blas García replaced the late Federico Romano as Darth Vader for "Spark of Rebellion", but in the series proper, he is voiced by Sebastián Llapur from season two onwards. The same goes for Emperor Palpatine, who is voiced by Jesse Conde after Jesús Colín retired in 2005 and subsequently passed away six years later.
Darth Vader's most famous French dubbing actor, Georges Aminel, passed away in 2007. He was replaced by Philippe Catoire, who also voiced him in Rogue One.
Ian McDiarmid took over as Palpatine after Sam Witwer voiced him in a single scene in the show's second season. In 2019, the version of "The Siege of Lothal" available to stream on Disney+ retroactively replaced Witwer with McDiarmid as well.
Clancy Brown has reportedly expressed disappointment in being typecast as villains (including Savage Opress in The Clone Wars) all the time, and even hated playing a vile prison guard in The Shawshank Redemption, so it's heartwarming here to see him playing the friendly Cool Old Guy Ryder Azadi here.
Liam O'Brien usually voices characters that are Ax-Crazy to some extent, bishonen, and/or sophisticated/well-mannered. Lyste is at least sophisticated (or tries to be), and so is Mr. Sumar to some degree as well.
Production Posse: Greg Weisman brought over a few voice actors from his previous works (particularly Young Justice), those being Steve Blum (Zeb and Count Vertigo), Vanessa Marshall (Hera and Black Canary, who was also a Team Mom — not to mention that she's Weisman's favorite DC character), Bryton James (Zare and Static), Eric Lopez (Oleg and Blue Beetle/Jaime; Lopez would also return as Jonner), Brent Spiner (Senator Trayvis and the Joker), Keone Young (Commander Sato and Sensei), Peter MacNicol (Tseebo and Professor Ivo), Clancy Brown (Governor Ryder Azadi and King Faraday). This mostly stops after Season 1 due to Weisman leaving the crew. Spiner, Young, and MacNicol are also Star Trek actors, which Weisman is also a fan of and has also done with this trope in his other shows.
Both Filoni and Hidalgo have admitted that some of the ideas the crew had brainstormed over (and decided to do, in some cases), are showing how much everyone of them is a Star Wars fan to the core. Probably the best example from Filoni:
Fan Question: Will Rebels see a younger and skinnier JekPorkins, and see how he became the man he is? Filoni:[laughing] Just to show you, that the creators of this show, are not that far apart from you...It has actually come up!
Freddie Prinze Jr. In interviews, he enjoys talking about different characters and their Character Development, and also gives out hints to what will come next. He has also watched Star Wars: The Clone Wars, adding that his favorite lightsaber fight in the entire franchise is Viszla vs Maul.
In an interview, Dave Filoni said that while the story had grown considerably beyond that, to the point where it might not even happen at all, Maul's appearance in the story was catalyzed when the writers realized they had a chance to have a duel between him and Vader.
Reality Subtext: Dave Filoni's father passed away just a few weeks before recording "Jedi Night" and "DUME", which greatly informed how the crew reacted to losing their own father figure and having to deal with it and keep going.
Dave Filoni's original plans for Star Wars: The Clone Wars were to have a cast consisting of a smuggler, his girlfriend, a Gungan, and a Jedi Master-Padawan duo, who would've been travelling across the Galaxy on a ship similar to the Millennium Falcon, with movie characters only occasionally showing up. This idea was rejected by Lucas, who wanted the main characters of his movies to be the focus. However, these plans, with a few modifications to the cast members, came to be the premise of Rebels eight years later.
Shortly after Revenge of the Sith was released, it was announced that there were two Star Wars television shows in development — one was an animated series set between Episodes II & III, and the other was a live-action series set in the period of time between the two trilogies. Whilst the live-action show never surfaced, the premise would be revisited as an animated series with Rebels.
Several previously unused Imperial vehicle designs had been refitted for the show, such as the AT-DP walkers.
The Imperial freighters are a newer, slightly modified version of the Gozanti cruisers that had appeared several times in the prequels and The Clone Wars.
The A-Wings in Season 2 are based on the original McQuarrie concept art, and some will have blue markings; which the models used in Return of the Jedi were to have before it was realized that it would blend with the blue-screens and stop the models from being implemented successfully.
One of the concepts that Filoni never got to use for The Clone Wars was a scene set during Order 66, where Ahsoka would be saved from the attacking clone troopers by an army of giant wolves that appeared to kill the clones. The giant wolves, now properly called loth-wolves, would later appear in the final season as allies and spirit guides for the main characters, and the " wolves murder the hell out of bad guys who have the heroes surrounded" scene would happen in "A Fool's Hope" when Pryce's forces have the Rebels on their knees.
Though Kallus and Saw have yet to interact onscreen but do have pasts that tie to each other, their voice actors, David Oyelowo and Forest Whitaker are friends and played together in The Butler.
The voices of cadets Zare (Bryton James) and Oleg (Eric Lopez) previously voiced young new heroes in Season 2 of Young Justice as Static and Blue Beetle respectively. Their debut episode, "Breaking Ranks", was written by Young Justice co-creator Greg Weisman.
Paul Reubens returned to voice pilot droid RX-24 (AKA the original Captain Rex) from the original version of the Disney Star Tours ride.
Steve Blum voices a number of Stormtroopers, like he did in a number of Star Wars games previously.
In Seasons 3 and 4, Forest Whitaker and Genevieve O'Reilly reprise their respective roles as Saw Gerrera and Mon Mothma from Rogue One.
In the final episodes of Season 4, Ian McDiarmid returns as the Emperor, after he was previously voiced by Sam Witwer for a cameo in "The Siege of Lothal".
Screwed by the Network: An example that occurred after it was confirmed that the fourth season would be the last, and that the series would get a proper conclusion. Like Motorcity and TRON: Uprising before it, the final season's timeslot was moved to 12:30/1:00 AM on a Monday morning, with two episodes every week. Star Wars Rebels receiving this treatment has been compared to that of the final season of The Legend of Korra, which was also placed in late-night timeslots with two episodes airing every week at one point until the last half of the final season was moved to the online website. Considering The Legend of Korra wasn't popular among the target audience of the channel (who are children) due to darker tones and heavier continuity in comparison to other shows on the line-up, the same likely applies to Rebels (and it's not like this is the first timean animated show in the franchise got screwed by the same issue). They seem to have scrapped the 12:30 AM timeslot, new episodes return to airing at 9:00 PM though still on Monday, but are still airing two episodes a week, most likely in order to burn off the episodes quicker.
So My Kids Can Watch: The other main reason why most of the newcomer (both in the voice acting business and to the franchise) adult voice actors like Prinze, Gellar, Oyelowo, Anthony-Rodriguez, etc. are involved. Combined with Awesome, Dear Boy.
In the Rebels Recon for "Vision of Hope", Dave Filoni talks about dropping clues to the audience about stuff like Fulcrum's identity, but also dropping misleading ones... while Fulcrum's symbol is right behind him.
In "Fire Across the Galaxy", the episode ends on the note of the Rebels boarding the Ghost to meet Fulcrum... And they come across Bail Organa, who was speculated to have the identity. About 30 seconds or so later, the actual Fulcrum (Ahsoka Tano) properly reveals herself.
Aftermath also contains an interlude chapter on Chandrila, where a character talks about an art-piece in the circle of the capital, Hanna City, consisting of Stormtrooper helmets painted over with Alliance insignias, starbursts, and flowers. She gets cut off before she can say the name of the artist. Huh.
And with Hidalgo's Propaganda book, it seems that the artist is indeed Sabine, who survives at least past A New Hope, becoming a famous Rebel propagandist.
During the wait between Season 2 and 3, prior to Celebration 2016 (as Filoni said that there would be a huge announcement regarding Rebels there), Filoni tweeted a picture of a spine of a Legends book. Fans managed to match it up with Heir to the Empire.
Ever since the public release of Sabine, fans had long been theorizing that she was the daughter of Rook Kast, based solely on their similar hairstyles, head shapes, and helmet markings. The assumptions since then had only increased once more of Sabine's backstory was revealed. It was not helped by Hidalgo openly saying on Twitter that Sabine's appearance was partly based on Kast, a Nite Owl (it already being known at the time that her mother was former Death Watch), an original color scheme, and "secret sauce".
And, of course, it turns out that Sabine's mother is not Rook Kast, but a new character, Ursa Wren.
Hera, Chopper, and the Ghost are in Rogue One? Awesome! But wait, why is the back of the Ghost, specifically, where a Phantom shuttle should be conveniently hidden from view...?
On a case bordering Lying Creator, when Star Wars YouTuber Dash Star interviewed Freddie about Season 3 and asked if Kallus is the new Fulcrum, Freddie hesitated for about a second before saying that he would love it and that he would be open to whoever Fulcrum is. Given that at the time of the video, Season 3 already wrapped up production and he should already know who Fulcrum is (unless it didn't get covered within the season), he clearly already knew and was avoiding the question. It's Kallus.
Upon being asked about the possibility of Zeb and Rukh duking it out, Steve Blum cheekily answered that it would be an interesting match-up. The Season 4 midseason trailer later revealed that they do indeed fight.
In the toyline, this was how Sabine's 6-inch figure was made. Hasbro held a competition for fans to choose the next 6-inch figure, with Sabine and Revan being two of the finalists. The race was so close between them that Hasbro decided to do them both.
In an interview with Jim Cummingsnote AfterbuzzTV episode for his first Rebels episode, he reveals that a combination of doing the voice work with the other actors there to work off of, and encouragement from the crew, ab libs are quite common, especially for Hondo. For example the "washed up old relics"/"your wife" exchange.
FPJ on one of his Twitch livestreams said that he might've (it was months since he recorded the episode, so he forgot if he did) made up the "I heard that!" response to Saw and Rex talking about how he's no Skywalker in "Ghosts of Geonosis".
Kanan's eyes clearing during his death wasn't originally part of "Jedi Night". Filoni was just drawing storyboards for the scene the scene and realized that he accidentally drew Kanan's eyes, then realized it fit the scene.
In the Rebels Recon episode for "Idiot's Array", Pablo Hidalgo is asked who Fulcrum is. He begins to explain only for the video to become corrupted and cut to a "please stand by" image, and cut to the preview of the next episode, leaving the question unanswered until the Season 1 finale.
In the Recon episode for "The Future of the Force", Filoni mentions that the Inquisitors were never a threat to Ahsoka during their fight with her. He then adds that there is a duel coming-up with much bigger implications for Ahsoka's fate. He then stares straight into the camera with such an evil troll grin it would make Sidious proud.
Filoni casually dropping that Ahsoka and the Bendu met after the events of "Mystery of Chopper Base", with the Bendu foretelling to Ahsoka that death/change will follow after learning the truth from the encounter on Malachor (yet implying that this death is not permanent or at least whatever Ahsoka may be thinking) and that this means goodbye for now.
A then-popular theory that Rook Kast was Sabine's mom was believed because of the amounting evidence by Word of God and other vague information... though one should have taken into suspicion that Word of Godwasn't even trying to hide Sabine's relation to Kast. The theory ended up being Jossed, with Rook's fate being currently unknown and Sabine's mother being a new character. While Word of God has yet to comment on it again, you have to wonder if they're making stealth takes at the fanbase by making having Sabine's homeworld be named Krownestnote Rooks and crows are closely related., and one of the clans that swears fealty to Bo-Katan near the end of the Mandalorian arc being named Clan Rook.
Voices in One Room: Like Star Wars: The Clone Wars before it. Of course, there are exceptions since some of the voice actors like Lars Mikkelsen and Tom Baker are overseas (the main recording studio being in California), in which case they record their lines in another professional studio with Filoni directing on Skype and send it over to Lucasfilm HQ.
Why Fandom Can't Have Nice Things: A multi-social media roleplaying group (that will remain nameless here) managed to get Freddie Prinze Jr. (and at least one other voice actor, possibly Vanessa Marshall) on their roleplay on Twitter back in Season 1. Apparently, these voice actors eventually found out about the group's notoriously unkind attitude towards others, and thus released a statement about how the fanbase should be positive and kind to others. They have since ceased interaction with the group.
Dave Filoni admitted that one condition Sarah Michelle Gellar had before joining the show was that Kanan, played by her husband Freddie Prinze, Jr., wouldn't be the one to kill her. Therefore, the Seventh Sister's death came at the hands of Maul.
In a Collider Jedi Council podcast and a couple of other interviews with Freddie, the voice actors already know what will happen to their characters, only waiting for how their stories will be executed (as in, they don't know the exact events that will lead up to those milestones until they receive the episode scripts). In a First Order Transmission interview, he even reveals that he knew as early back in the recording of Season 1 that Kanan would become blind at some point, but didn't know who would inflict it.
Sam Witwer revealed that he and Ashley Eckstein were given a rundown on what happened to their respective characters up to Revenge of the Sith.
It seems that the voice actors for the Inquisitors are not informed on what their characters have done and their future, but the writers on the other hand seem to know, as Jason Isaacs did not seem to be aware that the Grand Inquisitor was a former Jedi Temple Guard until he recorded for it, and Philip Anthony-Rodriguez was only informed that the Fifth Brother was European/Spanish-based and blind, nothing beyond that.
An IGN interview with Filoni after "ZeroHour" revealed that Kallus' story arc was planned from the start.
One of the writers has mentioned on a post-Season 1 finale interview that the show is structured by 3 acts, with Season 1 being Act 1, as well as that not all the acts will necessarily correspond to each season. Act 2 also begins with Season 2, but will not end with its season finale.
It has been said that a Mandalorian relations chart has been created by the writers for reference.
In "Imperial Supercommandos", when Rau describes Saxon as being 'part of Clan Vizsla, like [Sabine]', Hidalgo tweeted that the script should have said he was of House Vizsla and not actually from the clan itself.
As the members of Iron Squadron have names based off of John Harper (cameraman for The Star Wars Show), Andi Gutierrez (host of The Star Wars Show and Rebels Recon), and Matt Martin (member of the Lucasfilm Story Group), they recorded temp dialogue for the titular episode.
Before the airing of Season 2, Filoni had said that he wanted to do an episode that took place from the perspective of the Empire, but it wasn't supported enough by the other writers to do in Season 2. Instead, "The Honorable Ones" focused on Kallus away from the Empire, and eventually, we got "Through Imperial Eyes", which gave some insight on the inner workings of the Empire through the eyes of a rebel spy.
During the Season 3 to Season 4 hiatus, Filoni stated he always personally believed Kallus's first name is Alexsandr. This fact never comes up on the show at all.
Judging by interviews, voice actors of characters like the Ghost crew members are given a run down of what will happen to them. Voice actors of characters that don't appear long enough in Rebels (like the Inquisitors) do not get this luxury (these characters also don't seem to have set fates like how the Ghost crew members are already planned to live or die at the beginning of the show).
Upon the topic of how long the show will run, Freddie constantly says that the show will likely last for more than 3 seasons, even saying in one interview that they could last 5-7 seasons. First Order even has him pointing out that it wouldn't make sense for Disney to cancel a show from a Cash Cow Franchise. As long as there's are stories to tell, the show will continue, and once those stories are done, the show will end.
Freddie has revealed on his Twitch that by this, he means that Disney has given Filoni and co. a blank slate; the entire show was greenlit, meaning that it can be however long it needs to be, and that announcements about a season being greenlit are only to tell the press.
As of September 2016, they've been recording for Season 4 ever since July.
Back in Season 1, Freddie said that the story of Ezra getting his lightsaber would've been a two-parter, but this ends up being false. Either he was misinformed or this was the original plan for "Path of the Jedi".
Freddie Prinze Jr. mentions on Collider Jedi Council that in the finale, "Twilight ofthe Apprentice", once Kanan does a certain thing, he will have passed a Jedi trial, having already passed maybe two in Season 1. He's talking about how Kanan will lose his eyesight. In Legends, the trial is the Trial of Flesh, the third trial after Skill and Courage, before Spirit and Insight.
Sam Witwer has said that Maul was not entirely faking his weakness in "Twilight of the Apprentice", and while he doesn't show it his age is starting to catch up to him, hence why he wants an apprentice to pass on his legacy. He's also of the opinion (though he's not sure if the writers share it) that Maul sees Ezra as a sort of replacement for Savage.
In Season 1, Freddie's favorite character (besides Kanan and Ezra of course) was apparently Kallus. By Season 2 and Season 3, this list has extended to include Rau.
After Season 1, someone messaged Liam O'Brien on Twitter about returning to his role as Lyste, commenting that he should get a promotion. Liam replied that it'd be nice for Lyste, but probably not a good idea considering what happened to Aresko and Grint. This foreshadowed that Lyste would return in Season 2 with a promotion, as well as being a Butt-Monkey. Also became Hilarious in Hindsight/Harsher in Hindsight when Season 3 came around (which had not been recorded yet at the time), because while Lyste also returns, his final appearance is being arrested under a false charge of treason thanks to Kallus taking advantage of his ambition in that episode.
Right before Celebration 2017, Alan Tudyk expressed interest in voicing K-2SO in Rebels. Given that Season 4 was revealed to the final season and is now wrapping up production, however, it alas is not to be unless he joins the cast in the final episodes.
Alistair Petrie also expressed interest in voicing General Draven in Rebels as well, but unlike Tudyk, he stated this right after Rogue One premiered (and thus earlier on in the Season 4 production), so he's more likely to return.
In the promotional build-up for the show, Vanessa Marshall stated that Hera was personally hurt by Order 66. This was never explained, though it's easily inferable that hearing about Jedi, who were pivotal in helping her homeworld, getting executed and accused of crimes by the waning Republic would really shake her faith.
Filoni considered re-canonizing Starkiller from The Force Unleashed by introducing him into the show as an Inquisitor, but ultimately decided against it.
According to Freddie, the reason why some of the incidentals' lines sound Narmy despite them being capable of voicing the lines better is because the voice actors only did the lines as a joke and didn't think Filoni would actually put those lines in the final version.
An interview with Vanessa Marshall revealed that Jacen was conceived in the episode "Kindred", between Kanan and Hera's opening scene at dusk and their later scenes at dawn. Kanan's line "about what happened", which she cuts off with a kiss, was a reference to it which obviously couldn't be said onscreen.