As Gu Yuan's words fell, the hand seal in his hands swelled against the wind, becoming a massive, ten-thousand-zhang seal in the blink of an eye.
The enormous hand seal radiated a thick, ancient yellow glow, as though it could suppress all ages. Its aura made the hearts of the Xiao Clan's many Eight-Star Dou Shengs tremble.
The Emperor Seal Art was originally one of the Gu Clan's heaven tier Dou Techniques. In truth, only its final seal, the Ancient Emperor Seal, had reached the heaven tier. But Gu Yuan had mastered this technique for over a thousand years and had long since modified and reshaped it into a heaven tier Dou Technique suited to himself.
Its true power was likely no less than that of a heaven tier advanced Dou Technique unleashed by Gu Yuan, a Peak Nine-Star Dou Saint. If such terrifying might fell upon any of them, death would be all but certain.
Though they could not call this Gu Yuan's strongest attack, its power was absolutely not to be underestimated. At the very least, anyone who had yet to reach the Peak Nine-Star Dou Saint level would find it extremely difficult to withstand.
"My worthy son-in-law, if you can withstand this move, I'll admit defeat."
Across from him, a smile appeared on Gu Yuan's face. After his improvements, this Ancient Emperor Seal was even more terrifying than the version created by the Gu Clan's Dou Di all those years ago.
Of course, that was also because that Dou Di had created it casually. Even so, the might of this move could not be underestimated.
But Xiao Yan was his own son-in-law, after all, and their exchange was merely a spar. Gu Yuan would not go so far as to strike to kill.
Yet faced with such