The two walked on the River of Time.
Although they could step on the Water of Time, they didn't dare to walk too fast because they had to gather their internal Spiritual Power at their feet at the exact moment of contact with the water's surface, lifting their bodies up.
Thus, it seemed as if they were walking on the River of Time, but in reality, their feet did not touch the water's surface.
Just like the nine monks forming an array to trap Su Mu, they seemed to be sitting cross-legged on the water, but in fact, they constructed an incredibly powerful Space-Time Array beneath them and were sitting on it, not actually touching the water.
Therefore, the nine monks dared not change positions easily and could only remain seated, waiting for reinforcements.
The biggest problem with trying to kill Su Mu on the River of Time was figuring out how to cope with the suppression from the River of Time.
