HoYoLAB is the community forum for Genshin Impact and Honkai Impact 3rd, with official information about game events, perks, fan art, and other exciting content.
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I expect this update to arrive around August 16th or 17th.
There is a so-called "log-in event" going on.
On October 1st you get in-game a thingy to make soap bubbles with.
Star Rail has a "log-in event" currently going on as well.
Background video on how they made Azhdaha, the dragon : https://www.hoyolab.com/article/554283
I found this quite interesting, because I don't know much about game development anyway.
- There is a seller of kites in Liyue Harbour, selling kites. I assume that these are only available during the event.
- The dragon dance web event thingy https://www.hoyolab.com/article/25061234 gives a decoration : a house
- a code to be found on this official page : https://www.hoyolab.com/article/25091304
- Various codes I found :