Zue Du activated his mechanical armor's ability, which released hot steam as it enhanced his overall speed and power. Even with the augmentation, he found he could barely keep up with Xin Wuming's swordplay. Xin Wuming was as if using a hundred swords simultaneously.
Xin Wuming was using a sword art he learned from Echos' military library, Death Blossoming Sword. This martial art was at the High-tier Practitioner grade. Each swing of his sword created a revolving image of swords that made it look like a flower with blades for its petals.