Yesterday was Venti's birthday, many people were wishing him all the best, but I don't know a single soul who took his mail seriously. He said there, that there's a treasure is near some place, where "azure laying siege to a field of green, and the yellow of stone ornamented with viridian. A seaside cave wreathed in clouds? A floating island covered in forest that appears only at night?". Maybe there's a secret chest, or an ARG hint inside of one of Liyue domains?