When that enlightenment guy says what you see in the swamp... "we see people we lost, people we loved" all in past tense... Aang sees toph correct?
so given the fact that time is an illusion and so is death... perhaps (and this is a long shot) that's a foreshadowing of toph dying in the series, aang saw toph in the swamp because he lost her, and since time is an illusion he's seeing a vision he would see much later.
Also strikes up a theory of aang loving toph, but I'm not sure you have to see people you loved, just people you lost.
I dun kno, whadda u think
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