In this world, there's a saying that doesn't hold true.
And that is, books are the stepping stones to human progress.
In this world, Wen Ping thinks that transportation is the stepping stone to progress, so if he didn't lack White Crystal, he would surely choose to upgrade the sail, crafting a five-leaf sail for the Flying Ship.
"Right, system, there's no restriction for upgrading to a five-leaf sail, right?"
At this time, he remembered that last time when upgrading the Flowing Cloud Armor, there were indeed restrictions.
"There are."
The system responded, and the sail upgrade interface opened up.
Besides the conspicuous upgrade cost of 500 pieces of White Crystal,
The restrictions were clearly visible.
He needs to fly fifty thousand miles to upgrade the sail.
However, upon seeing the distance already flown, Wen Ping sighed in relief—470,000 miles out of 500,000 miles—only three thousand miles short, which could be completed with a random flight.
