Boss farming optimization route in Liyue (Southwest)
There are many field bosses in Genshin. Boss materials are very important to ascend your characters & weapons, level up their talents. Of course, it consumes really a lot. Liyue has more bosses than Mondstadt, so to farm boss materials, you need to visit Liyue. Liyue is so huge area. I did not check other routes except southwest Liyue.
Don't mind about pickax icons. It's my personal mining place :) I did not note what kind of boss they are, but anyway all of them are important so just farm every boss. You'll find Rock Shieldwall Mitachurl, Fatui Pyro Agent, Ruin Hunters (both ground and flying types), Geovishap Hatchlings (I call them lizard), Fatui Skirmishers, Whopperflowers, Abyss Mages, Fatui Electro Cicin Mage. It will take long, but rewards are worthy. Dont' give up!