As soon as Old Master Ning left, Jiang Ying arrived. He looked anxious as he looked for Gu Yu and Ning Yue. "Divine Doctor Gu, I have something I need your help with."
"What do you want?" Gu Yu asked.
"Prince Qi and Prince Ning have joined forces to rebel. They're about to take down the border city."
At the mention of the border city, Jiang Ying's face turned pale. The border city was the most difficult city to take down. If the border city fell, it wouldn't be long before they attacked the capital.
"The border city's geographical location is dangerous. That shouldn't be the case. Did someone in the border city betray us?" Ning Yue asked.
If it wasn't a betrayal, she couldn't imagine why.
"It's poison. It's a mixed poison that appeared twenty years ago," Jiang Ying said.