Xuan Zhenzi fell silent for a moment, seemingly weighing his words.
Only after a long while did he drawl, "Your Highness the princess has reached the peak of the Fifth Realm, nearing the very limit of heaven-and-human resonance. Her foundations are profound, and her exalted status brings fortune to her side. Subduing her through sheer force would be as difficult as ascending to heaven."
The flame of hope that had just kindled in Wu Youji's eyes instantly dimmed.
"However..."
Xuan Zhenzi changed tack. "It is not entirely impossible. Among the cultivation methods of this world, where there is yin, there is yang; where there is strength, there must be weakness. The Purple Tenuity Heavenly Heart Formula Her Highness practices originated from Emperor Taizong's Imperial Pole World-Reordering Art. It follows the grand, orthodox path, gathering nine-five dragon qi, supremely unyielding and supremely yang, unmatched in power. Yet extreme yang gives birth to yin, and excessive rigidity makes for easy breaking. This cultivation method has one hidden flaw..."
Wu Youji's eyes lit up.
Though Wu Zetian had never taught him the cultivation methods of either Li Tang or the Wu family, he had gleaned a few things from Wu Chengsi and Wu Sansi's conversations.
Powerful though this cultivation method was, it did indeed have a weakness.
Xuan Zhenzi continued, "...On every full-moon night, the supreme yang energy within her reaches its peak, bringing on the phenomenon of 'the haughty dragon has regret.' Her true qi briefly reverses its flow, battering the vital passages of her heart meridian. This is the critical juncture in her cultivation method's circulation, when flourishing power turns toward decline, and also when her defenses are weakest. Mishandled, it could damage her cultivation at best, or... injure her very foundation at worst."
Wu Youji's breathing abruptly quickened, and a