Alright. In the mob_drop item file, the following items were assigned to the boss with ID 2307:
Soul stone
Blessing Scroll
Thief's gloves
Zen Bean
exp ring
Lord Ghost Tree Chest
Enchant item...
And after one restart, the items shown in the picture appeared, including item with ID 1, called Yang, and the item with ID 2, named in the English version, plus low-level weapons...
After I removed the drop of the boss with ID 2307 from the mob_drop_item.txt, the items listed above disappeared from the drop list, but the items shown in the picture still remained.
And there was no duplication of the mob in the mob_drop_item.txt...