Su Zimo who had just entered Level 4 of the Ten Formations Pagoda did not know that someone had cleared it previously. He did not know that there were more Array Peak disciples gathered outside and that he was starting to gain attention as well.
Level 4 was the killing formation.
Amongst the formations, killing formations were the most powerful. If a cultivator was stuck in it without any means of dispelling and he wasn't strong enough, he would definitely die within.
Cultivators could hold out temporarily against the formation. However, there would come a time where they would get exhausted and by then, they would be destroyed by the formation.
However, killing formations were the easiest to dispel across the various formations.