The sound waves produced by merfolks could cause great damage to creatures, and when dealt to humanoid machines, the damage would be directly doubled!
Under the impact of the sound waves, the three-star and four-star humanoid machines completely lost their combat ability. Their shining eyes dimmed and they fell heavily to the ground.
The situation of the five-star and six-star humanoid machines was not much better. Although they still persisted, it could be seen from their flickering eyes that they would not last long.
Since the people in black targeted alchemists, they naturally knew that dwarven alchemists were best at building humanoid machines, and at the Alchemist Convention, there were a lot of powerful alchemists. How could they not have powerful humanoid machines in their hands?
Evidently, the men in black were fully prepared before they attacked.