Yang Jing took out the various Cultivation Techniques he possessed. Through his experiments on Iron Head and Yinjiao, he had discovered that the compatibility between a Cultivation Technique and a Guardian Beast was extremely important.
This was because the number of Spirit Stones required to enhance each realm would skyrocket fivefold compared to the previous one. A high or low compatibility might only mean a difference of a few, or perhaps a dozen, Spirit Stones when strengthening the first realm, but this would balloon into an astronomical figure in the later stages.
If he had Iron Head cultivate the Twenty-Four Solar Terms Swordsmanship and reach the Peak Realm, it would cost far more than the six thousand-odd Spirit Stones it had taken for Yinjiao.
By the same token, Yinjiao's study of Alchemy wasn't the smooth success it was for Iron Head. To this day, he still fumbled when refining Blood Circulation Pills.
