Ornamental Gold Dream Genshin Impact is an artifact set that is rumored to be released in version 3.0. You can get this artifact in Sumeru.
Ornamented golden dream set bonus
|2 piece set||Increases Elemental Mastery by 80.|
|4 piece set||the effect manifests itself after the elemental reaction. 1/2/3 characters of the same element give the wearer of the artifact x/x/x% to ATK, while 1/2/3 heroes of different elements cause the wearer to gain x/x/x elemental mastery. The bonus lasts 8 seconds and can be triggered every 8 seconds. It can be called even if the wearer is not on the battlefield.|
More information with the release of update 3.0.