Heavy Horn

To obtain a Heavy Horn, you need to find and kill Mitachurls at any level. Upon eliminating these fighters, they have a chance to drop Heavy Horns.

You can get these from any of the Mitachurl family, no matter the Element or the size.

The fastest way to get around is to use the Waypoints and travel around the entirety of Teyvat. Kill everything in sight, and then move on. The images below are the locations you can find Mitachurls.

A crude horn used by hilichurls to warn each other. Given the damage to the horn, it won't be warning anyone any time soon.