Fang Hong observed from the shadows; the power of this Falling Thunder Immortal formation was indeed impressive.
The lightning power was fierce and overbearing, and each strike caused a significant impact on the Purple Flame Serpent.
However, even so, it was probably unrealistic to directly kill the thick-skinned Purple Flame Serpent with this formation.
The blue-robed youth and the White-Robed Female Cultivator clearly knew this as well, and they immediately took out two crystal-clear Immortal Stones.
The two held the Immortal Stones in their hands, guiding the Immortal Power from the Immortal Stones to continuously flow into the blue banner, fully maintaining the operation of the Immortal formation, keeping the lightning power within the formation at its peak state.
At the same time, they each summoned a Flying Sword, conjuring hundreds of sharp sword shadows that fiercely attacked the Purple Flame Serpent within the formation like a torrential rain.
