Yun Zimo was protected by an invisible so that he didn't die from the explosion of Souls and Soul Treasures.
The cave then collapsed and the sunlight could finally reach the cave walls. From within the rubble, Yun Zimo was safe within and the bubble barrier rose in the air and flew towards the centre of the explosion. When the dust settled, Huang Jun's Soul was actually still alive but extremely weak at the moment.
Various factors had contributed to it being so weak, firstly, whatever mysterious attack Zixin had used on him that almost killed him, second was the explosion from the veiled woman, the third factor is when he detonated the Soul Treasure and the fourth and final factor is just now, to protect Yun Zimo really did a toll on him, otherwise, he would be much better than his current state.
