647 The Grand Reaper, We Will Fight it Side by Side!

Yowl!

Yowl!

Beyond the endless rows of Undead Horde…

Not very far away from the front line, a wailing, intermittent cry that belonged only to the nether world began to echo across the entire warzone.

The undead creatures, as if frightened by their worst nightmare, started to distance themselves away from the source of the wails. They squeezed hard in the opposite direction even after they stumbled upon other Specters.

The situation in the air was equally hectic.

Not a single creature dared to fly above the sound source, be it Skeletal Dragon, Vampire, or the prestigious Lich. These flying monsters either changed direction immediately or directly halted and turned away as soon as they heard the cry or saw the numerous skulls "fizzling" from the ground.

This was the reason behind the mysterious appearance of a hundred-meter wide empty area deep within the Undead Horde.