The Siege of the North (Part 2) - S1-E20
Question: When Aang is told by Roku that he must ask questions of the centipede monster, why can't Roku ask the centipede monster the questions, then relay the answers to Aang? Roku is already in the spirit world, and would have course have much more experience in these matters. Aang is already taking on enormous burdens simply by knowing his full identity at 12 instead of, as they say several times, 16, then having to train by going on this enormous journey.
Answer: As the Avatar, Aang's main function is to be the bridge between the spirit world and human world. Roku, being a former Avatar knows that Aang has to learn how to interact with spirits. He's certainly under a heavy burden but that's mainly his fault for running away from his responsibilities in the first place. Difficult or not, this is simply a lesson Aang must learn.
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