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For the residents of Safety Sky City, it was an ordinary day.
However, it was at this moment that the melodious sound of a flute came drifting from afar.
This flute music seemed to possess a special kind of magical power, both melodious and deep.
It was unknown who was playing it.
Soon after the flute music began, an inexplicable "rumble" followed closely behind.
This "rumble" started off quietly, resembling the sound of a drum.
But as time went on, it grew louder and louder until it was like the roaring of thunder, with Heavenly Thunder crashing down.
It wasn't just the noise; the ground itself seemed to start shaking and trembling.
The morning breeze blew gently, as for those living in Safety Sky City.
Here, far from the Imperial Capital, the pace of life was frighteningly slow.
At this time, apart from a few people who had gotten up early, most of the residents were actually still asleep.
But as the noise outside grew louder and louder, no one felt sleepy anymore.
