"I'm sorry. I'm at my breakthrough stage so my energy is unstable," Ling Lan replied calmly.
So that was what was happening!
Yu Huan and Ke Yufeng felt enlightened. They experienced this stage before. To increase the success rate of advancing, they suppressed their Qi-Jin energy until there was enough accumulated. When everything was prepared, they would then focus on their breakthrough. It was not easy to suppress the overpowering Qi-Jin energy. Sometimes, they needed to use all their concentration to suppress it, causing them to lose awareness of what was happening around them. It was as if they were sleepwalking.
This would explain why the killing intent on Regiment Commander Ling was so strong at the beginning. It must be because he couldn't suppress his energy fully so some of it leaked out. Even when he successfully retracted his killing intent, his cold aura leaked out.