Talk about sacrifice: eating in costume every day.
“Ewok” was never actually said in Return of the Jedi, the name was learned from merchandising. The plan was to have a wookiee army, but when the change was made, the ewoks were made small in contrast to the oversized wookiees, and they got their name from flipping around the name “wook-iee” to “e-wok.”
Han and Greedo chilling
In an attempt to avoid spoilers the shooting script actually had Darth Vader telling Luke that Obi-Wan killed his father. It was only changed when James Earl Jones recorded his lines in post-production.