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The crystal ball at the front of the Dragon Abyss Boat has a white stone strip. When the boat is on the surface of the water, the strip is white. As soon as it submerges, it immediately turns blue, gradually turning red from one end over time. When it's completely red, it indicates that the air inside the boat is insufficient and it must surface to replenish.
Breathing in the moist air above the sea, Ning Rongrong exclaimed, "This Dragon Abyss Boat would be worth it even for 100,000 golden soul coins, not to mention 10,000. Except for lacking offensive and defensive capabilities, it is nearly perfect. Had we known it was this useful, why would we have bothered renting a ship to go out to sea?"
Tang San smiled slightly and said, "That would still require a sea chart. The sea chart we currently have is the culmination of many years of navigation by the Purple Pearl Pirate Group on the high seas. We didn't have such a fine thing when we first went to sea."
