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Co-op Mode Warning

Hoyoverse hasn't put out an official announcement yet, but this is a serious issue, so I'm taking some liberties here. Do not let anyone you don't know into your world for now! There is a recently discovered exploit that allows hackers to use Kaveh and a third party app to permanently remove content from your world. So far, it's only been recorded in Chinese servers, but until we have confirmation that it's fixed, I recommend rejecting random co-op requests to be safe. Video evidence here.

The removal is on the server side, so logging out or uninstalling the game will not restore lost content.

For clarification:

Update: Some sources also say Nahida can be used for this, but take that with a grain of salt.