The underground city existed to be conquered.
Returning along the original path, one could see a passage that had never appeared before, a design intentionally created to allow the conquerors to perceive the strategy for overcoming this underground city.
While explaining to Iyas, Yang Yu lightly touched the wall at the end of the passage, causing the light on the wall to suddenly brighten, revealing the number 6 composed of horizontal and vertical lines.
"What does this mean?" Iyas asked.
"This is the key needed to open the next passage. Iyas, with your long legs, we need your help."
"What kind of help requires long legs?" Iyas asked.
"Tool Man."
"Tool Man? What Tool Man?"
"A human pedometer."
Turning away from the passage, the corners of Yang Yu's mouth kept curling upwards.
If one didn't understand the strategy, it might be very difficult, but once understood, it was just like that, almost all puzzle games were like this.
