Although on the surface, Zhou Tian indeed already possessed the ability to take down the Light God King in one move. However, in reality, if Zhou Tian truly wanted to capture the Light God King, it wasn't impossible based on his strength, but doing so was not as simple as Zhou Tian thought.
Who doesn't have a few hidden trumps? The more powerful the living beings, the more they would prepare some abilities that couldn't see the light of day. Usually, these abilities aren't used in battle, but if they encounter danger one day, those hidden abilities might save their lives.
Zhou Tian has quite a few hidden trump cards, and he is just a novice among the Divine Kings. For those veteran Divine Kings, in a situation where they can't break through, it is impossible not to prepare a few more hidden trump cards for themselves.
