What did Yoda do between Revenge of the Sith and Return of the Jedi? We'll find out in an upcoming episode of Star Wars Rebels when we encounter Yoda once again—sort of.
TV Guide has announced that Frank Oz will be lending his voice to Yoda once again for Star Wars Rebels, which is great news because we're only getting Yoda in the form of a disembodied voice. Yes, Yoda is still off on Dagobah, but he hasn't stopped being a teacher to young Jedi. He'll be reaching out with his mind to lend support to Kanan and Ezra.
According to executive producer Dave Filoni, it's a way to allow Yoda to interact with the fledgling Jedi and his master while keeping him on Dagobah:
"I felt personally to keep Yoda as this disembodied thing it would confuse the audience less," says executive producer Dave Filoni, who also directed the installment. "I didn't want you to think Yoda could be teleporting from planet to planet."
Yoda's voice will appear when Rebels returns from its mid-season break on January 5, 2015, in the episode "Path of the Jedi."