Rebels - S1E8 - "Gathering Forces"

9:04 - Hera (to Kanan in the Phantom):  "Detach!"  Han gives the same order to Chewbacca in The Empire Strikes Back, to separate the Millennium Falcon from a Star Destroyer as the Imperial fleet breaks up [1:15:50].

14:05 - An Imperial Star Destroyer flies overhead as a shuttle exits it, which is the same way that Return of the Jedi starts:

14:37 - Grand Inquisitor (to a group of stormtroopers, referring to Kanan and Ezra):  "I want them alive."  Vader gives the same command to the stormtroopers in A New Hope ("Bring me the passengers; I want them alive!" [6:08]) and to the bounty hunters in The Empire Strikes Back ("You are free to use any methods necessary, but I want them alive, no disintegrations" [1:06:14]).

18:10 - Ezra:  "I feel so cold."  This comes after an experience with the dark side of the Force, so it's similar to Luke's reaction to the cave on Dagobah in The Empire Strikes Back where he says, "I feel cold" and Yoda explains, "That place is strong with the dark side of the Force.  A domain of evil it is." [1:02:43]

Rebels - S1E7 - "Empire Day"

2:28 - In the interior of Old Jho's Pit Stop there's an-other use of the hexagonal pattern seen in the homestead garage in Attack of the Clones and A New Hope:

8:58 - Stormtrooper (to Ezra and Kanan):  "Move along."  In A New Hope, a sandtrooper says the same thing when, prompted by Obi-Wan's influence through the Force, he directs Luke into Mos Eisley:  "Move along.  Move along." [43:51].

15:54 - Commandant Aresko:  "That's far enough, rebel scum."  An Imperial officer delivers the same insult in Return of the Jedi:  "You rebel scum" [1:33:51].

16:10 - Kanan (to Sabine, who's driving the Imperial transport):  "Punch it!"  Han also says this to Chewbacca in The Empire Strikes Back [35:35].

20:44 - Zeb (referring to Chopper):  "Is that scrap heap even paying attention?"  In A New Hope, C-3PO similarly insults R2-D2 and calls him a "nearsighted scrap pile" [9:56].

Rebels - S1E6 - "Out of Darkness"

3:59 - Kanan:  "If she [Hera] trusts the contact [Fulcrum], I trust the contact, no questions asked."  Obi-Wan also uses this phrase in A New Hope while securing passage to Alderaan; after Han asks about the cargo, Obi-Wan replies, "Only passengers:  myself, the boy, two droids, and no questions asked" [48:23].

14:31 - Hera (to Sabine):  "So what's your plan?"  In A New Hope, Han asks Luke the same thing:  "What's your plan?" [1:11:56]

Rebels - S1E5 - "Breaking Ranks"

0:24 - Taskmaster Grint (presenting the cadets to Commandant Aresko):  "Squad LRC-077 for your inspection, sir!"  This may be a reference to 1977, the year A New Hope was released.

0:37 - Commandant Aresko (to the cadets):  "By the time you complete your training, you will be prepared to serve your emperor."  Vader uses the same expression in The Empire Strikes Back when he tells Luke, "Join me, and I will complete your training" [1:50:39], and the Emperor uses it in Return of the Jedi (also speaking to Luke):  "I am looking forward to completing your training" [1:31:04].

17:42 - Jai Kell (after a tank fires at the walker they're inside):  "Fire back!"

Zare Leonis:  "I'm trying!"

Leia gives the same response to Han in the trash compactor in A New Hope [1:23:41]; Han says, "Get on top of it," and Leia replies, "I'm trying!"

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The symbols that the cadets have on their helmets (and the helmets themselves) are reminiscent of a Ralph McQuarrie concept painting for The Empire Strikes Back:

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