Inside of the large formation was full of purple ancient Lightning Spells. The rumbling of the thunder caused one's heart to tremble.

Xiao Yi was surprised by the Thunder Array because he was able to break through the Zhen Formation when he was about to refine the Roaring Sky Print. It meant that Xiao Yi could use the Ancient Lightning Spell in the Fire Dragon Cauldron to refine his weapons. In this way, the power of the Roaring Sky Print refined by Xiao Yi would naturally increase significantly.