A Yellow Tier skill required a Warrior's cultivation base, and many Warrior Spirit Powerhouses were still cultivating Yellow Tier skills and techniques.
Only Warrior Spirits could control a Mystic Level Skill Cultivation Method. There were also a few geniuses who could control Mystic Level Skills when they were still Warriors.
As for Earth-rank skills, only Martial Kings could use them. Moreover, Earth-rank skills were all the treasures of a sect.
Not to mention Martial Kings, even Martial Grandmasters did not necessarily have Earth-rank skills to cultivate. Earth-rank skills were only cultivated by a very small number of Martial Kings and Martial Grandmasters. They were priceless.
For example, Li Lingtian's Warrior Spirit possessed a few Earth-ranked skills. It was already heaven-defying among heaven-defying skills. Furthermore, he had mastered a few Earth-ranked skills.
"This skill is useful to me."
