For ordinary grade one heavenly alchemists, no matter how skilled, they could only refine upper third grade quality too.
Those who could reach fourth grade were all heaven-grade powerhouses.
But the moment Lin Lan took action, it was upper fifth grade. It could be seen how profound his skill level was!
It was not that fifth grade was two grades higher than third grade; the quality would increase by less than twice.
The higher the quality, the harder it was to achieve.
Third grade to fourth grade was several times the gap.
Fourth grade to fifth grade was another gap of several times!
This kind of disparity was magnified exponentially.
Fifth grade compared to ordinary third grade, the medicinal effect was at least more than ten times stronger!
Further up, it was virtually impossible for a grade two heavenly alchemist to want to reach sixth grade.