So we know that Seren is millions of years old, as stated in the cutscene at the beginning of Desperate Times. This means that she, Zaros, and the current cycle of the universe are hundreds of times older than Gielinor. And since the Dragonkin and Elder Gods are from the previous cycles, they're even older than that. Pretty interesting. I was honestly surprised to read how old the universe was. Everything until then seemed to be only several millennia old at most. Not thousands of millennia.
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