The mental attack from the sound made the increased consumption of energy by armaments become a massive disadvantage for the disciples of the Blood Skull.
Despite all the difficulties that everyone faced, some disciples still managed to withstand all of these difficulties and reached the edge of the fourth section.
Most of them were from the Blood Skull sect even though they now had a massive disadvantage. This was all because the disciples at the third mortal coil had more energy than usual.
But there were one or two people from other sects who were talented enough to reach edge of the fourth stage too. It wasn't just the disciples of the Blood Skull sect who made this achievement.
If 100 people out of the total 1,000 in the ruins managed to reach the edge of the fourth stage, 90 of them would be from the Blood Skull sect. The remaining 10 places would be shared among the other four sects, of which 5 of them belong to the Black Bones sect.