[Thus, five more years passed...]
[In the one hundred and fiftieth year, you thoroughly repaired the Flowing Cloud Golden Light Boat...]
[With years of artifact refining, your artifact refining skills had improved, and you were now capable of attempting to refine top-grade Immortal Treasures...]
[However, the materials needed for top-grade Immortal Treasures were exceedingly rare!]
[To refine a top-grade Immortal Treasure, the material costs were nearly a billion high-grade Spirit Stones, over ten times the cost of refining a high-grade Immortal Treasure...]
In the real world, Su Xing saw this and nodded slightly, saying:
"Nearly a billion high-grade Spirit Stones... that's tens of millions of top-grade Spirit Stones!"
"Only a True Immortal could possess such wealth, right?"
Top-grade Immortal Treasures were originally meant for True Immortals, to be able to unleash their maximum power.