One reason many of us enjoyed "Star Wars: The Force Awakens" is because it returned a handful of iconic characters that we have come to revere over the years. Yet one character that was not brought back was Darth Vader. The Dark Lord has been dead since "Return of the Jedi," so it makes sense that the only remnant of his character in the new film is the charred remains of his helmet. However, at one time, J.J. Abrams was planning to include a recreation of the famous lightsaber duel between Luke Skywalker and Darth Vader on Bespin.
According to Making Star Wars, Rey was supposed to witness the fight during her Force vision in Maz Kanata's castle. While the scene did not make it into the final film, a new "Star Wars" novel, "Rey's Story," makes reference to what she would have seen.
"As she peered into the distance, she saw a man in black wielding a red lightsaber. His face was covered with a mask, molded to approximate a human face. But the mask's eyes were dead and empty. The man's red lightsaber clashed against a brilliant beam of blue. A young man with blond hair raised his own lightsaber and fought furiously against the monster in black."
Rey would not have understood the context of the scene given her unfamiliarity with the characters at the time. However, audiences would have remembered the battle well from "The Empire Strikes Back." But given Luke's minimal role in "The Force Awakens," it's understandable why this particular flashback was eventually cut.
Though Vader was ultimately not featured in "The Force Awakens" - something Abrams considered - it is rumored that Hayden Christensen could return for a cameo in Rian Johnson's "Star Wars: Episode VIII." Unfortunately, we'll have to wait quite a while to find out as "Episode VIII" won't arrive until Dec. 2017.