Yang Bo said, "This is a good chance to use up the low-quality Energy Stones I've been stockpiling." He had quite a few Energy Stones on hand.
The ones he was using now were the poorest quality and smallest in size.
The Machine Insect was not large to begin with, and the device holding the Energy Stones required isolation measures to prevent the Energy Fluctuation from leaking out.
Yet even the lowest-quality Energy Stones were not cheap.
Excavating this tunnel had used up two rice grain-sized Energy Stones.
Although this downward tunnel was only 500 meters long, it was 2.2 meters high and 1.8 meters wide.
Within such a volume, the Machine Insect had to keep cutting out chunks of stone. Every chunk required the insect to excavate back and forth countless times.
Yang Bo had set the Machine Insect's excavation width at just ten centimeters per pass. For a simple cross-section 2.2 meters high and 1.8 meters wide, the Machine Insect's total cutting distance had reached 396 meters.
At a height of 2.2 meters and a cutting width of ten centimeters each time, it had to cut back and forth twenty-two times, with each pass spanning 1.8 meters.
The cutting depth was also twenty centimeters. A 500-meter-long tunnel required cutting 2,500 cross-sections.
So while the thing was small, it was truly fast at work.
The reason he cut the stones so small was mainly to make them easier to wash away.
This time, Yang Bo took out slightly larger Energy Stones and placed them in the Machine Insect's Energy Stone compartment.
There was already water in the tunnel now, and the flow was quite strong.
Yang Bo also replaced the Machine Insect's work module.
The effect of this work module was grinding. It was an eight-centimeter-diameter grinding module. The