Light and darkness were two of the seven fundamental elemental Laws. Vidas' Nature Magical Domain also involved the nomological power of light and darkness. However, he only made use of the derived Laws of these two elements. Fundamental elemental Laws were closer to the essence of nomological power, so they naturally suppressed the power of Vidas' Magical Domain to a certain extent.
With the difference in levels in the Legendary-realm, it was almost impossible to establish one's own Magical Domain in another party's Magical Domain forcefully. However, Lin Li had done it. Although he struggled to control the usually tame magical elements that started resisting his control now, his Light and Darkness Magical Domain still expanded in the Nature Magical Domain slowly but steadily.