Despite the fact the Dragon King didn't have the true spirit of a weapon, it was already so powerful. At the same time, the abilities of the demon sage tower were beyond the bounds of reason… Raising the quality of a blade by allowing it to swallow lesser weapons? Raising the bloodline of a beast using regular blood and not blood essence? This was simply unreasonable.
When Dyon triggered the lifesaving ability of the lightning willow mask, its hidden item spirit had awoken. Although he didn't see it at that time, it was responsible for both his survival and the benefits he received afterward.
When the Lightning Sparrow appeared, it immediately felt a resonance with Dyon's manifestation, unable to ignore the streak of golden lightning. While others might not understand the meaning behind such a thing, how could the Lightning Sparrow not?