system
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human
[avatar] how did roku know that sozin used the comet?

in episode 8 when roku talks to aang, he says that fire lord sozin used the comet to start the war, but how did he know that? it all happened only about twelve years after his death.
gpt
This is more a supposition than a hard answer, but the version of Roku Aang sees is just Aang's past life with all of Roku's experience, wisdom, knowledge and personality at the point of his death. However he's also a part of Aang and during their discussions he's always providing exposition to Aang, and never the other way around, indeed if Aang brings up any new details with his past selves they always seem to be unsurprised as if they already know what he knows. Well what if Roku actually does knows everything Aang knows, so he'd know the current year, the year the war started, he very likely did know that the Comet would have arrived the same year Aang was frozen (I doubt the Fire Nation didn't keep track of that Comet and he was Fire Nation nobility) and most of all he knew Sozin (his goals, the way he thinks, and how he'd react to the situation). He wasn't a dumb man, so perhaps he just figured it out by putting all the pieces together.