Gu Cheng understood in an instant.
That was it!
Everyone had fallen victim at the same time.
It had to be a special kind of attack.
In plain terms, only an area attack could affect so many people at once.
Sound was one kind of area attack!
He recalled the breeze that had suddenly blown into his face earlier. He had wondered at the time how there could be wind in the tomb passage.
Then he had heard faint music.
He looked again at the holes in the rock wall!
He immediately understood what they were for.
Those densely packed holes were probably all connected, forming a natural musical instrument. When wind blew into the holes, it was like playing an instrument. The terrifying thing was that the music it
produced could unsettle the mind and stir up emotions.
The music was so quiet that it normally could not be heard.
He could only hear it because his senses were sharp.
But thanks to the Spirit-Clearing Pendant, the music had not affected him. Yet he had gone looking for trouble, insisting on moving up beside a hole to listen. The increased intensity of the attack had overwhelmed even the Spirit-Clearing
Pendant, so he had fallen victim too.
No wonder he had felt restless and unsettled after listening.
Gu Cheng had heard about this before.
In a sense, music was a kind of mental spell.
It could stimulate the mind, giving rise to all sorts of thoughts and ideas.
Science had confirmed this too.
Music had a direct effect on neural structures, particularly the cerebral cortex.
Differences in a piece's melody, tempo, and pitch could not only improve cerebral cortex function but also regulate cardiovascular activity, respiration, endocrine function, digestion, and bodily
movement, making people calm and composed, relaxed and happy,