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- Who is the most powerful user of the Force? 12 answers
In this interview from 1999 when asked why Darth Vader is a favorite character among children George Lucas says;
"... and who is more power than Darth Vader? Some will be attracted to Luke Skywalker because he is the good guy, but ultimately we know that Darth Vader is more powerful than he is. As time goes you discover that he more powerful because he is the ultimate father, who is all powerful."
Looking at this question Who is the most powerful user of the Force? there many answers in the primary canon and Legends canon on who that might be.
Does this quote from Lucas give us a clear answer that Darth Vader is the most powerful, or is Lucas' quote being given in the narrow field of Darth Vader vs Luke Skywalker? I understand this George Lucas we are talking about... so there might be a contradiction in another interview or something was ret-conned at a later time!
Also, at the time the interview was given I think the answer would be limited to Episodes I-VI. Answers would have to come from G-canon.