From what we've been able to tell, it is because the energy of liminal space and the maleability of it is very similar to Questing Country - that is, the collective dream world where we first learned to make them.

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Gil is the one who told me that you and he had undergone the same ordeal. Given how he needs to Harvest, I suspect he would be interested in trying to draw from a dreamcatcher instead. Anyone can draw from any dreamcatcher, too, so he needn't make one of his own if he doesn't wish to.