Li Mingwu gritted his teeth for like two seconds then wore a solemn smile. With a colossal boulder hanging over their head any other hunter would have felt like shitting their pants. Upon discovering that their opponent had not been taking them at full strength all the while and half of the landscape of the entire gate was overturned.
Such realization was bound to cause one to die from their minds before the hands of their enemy.
But another thing that set Li Mingwu apart from others is the state of mind. His experience over the years of course greatly contributes to that. Just like how you can't expect a novice hunter who had never been to a gate before to react and handle a monster the exact way a veteran hunter would.
In the face of such magnifying disaster, Li Mingwu was very calm.
But that had no effect on his surroundings, nor did it change the fact that what is about to happen is about to happen.