In Du Chengfeng's understanding, Evil Qi is called Evil Qi largely because it resembles gases.
Although he still hasn't figured out the principle behind Evil Qi entering the body, he has a deep impression of the sensation of releasing Evil Qi—it is simply about channeling the Evil Qi that has entered the body through a weapon as a medium to release it outside. Whether it's the fiery blade of the Heavy Great Saber or the cold wind of the Ancient Great Axe, or the invisible edge previously swung by the Broken Horse Long Saber, and Cui Yuan's sword glow... although their manifestations differ, their essence is the same.
Even the new halberd he acquired is like this.
