I've dropped Kingdom a few years ago, so Idk much about the arcs like Western Zhao Invasion, but for me chapter 212 was really peak.
The author introduced the full potential of Kanki as a general, first by showing how he would deal with a negative IQ brute commander like Kai Shi Bou, using some kind of numbered formation, splitting the army and attacking Kai Shi Bou's food supplies and isolated small armies, then using his evil way to torture the enemy's army, this would easily break Kai Shi Bou's army's morale, and Ka Shi Bou clearly wasn't someone who could deal with such tactics.
Second, when his spy told him that Commander Gen Pou had taken over the leadership of Ka Shi Bou's army, and that Commander Gen Pou had found out where Kan Ki's headquarters was, and had moved Ka Shi Bou and almost the entire army into a direct attack. Most commanders would retreat and defend the headquarters, but he didn't retreat, But disguised himself and his army as Wei's messengers, which was a very unorthodox strategy, but quite effective against scum like General Pou, who thinks the battlefield is a strategy book.
Kan Ki reminded me a bit of Liaoyuan Huo, who had a strategy of baiting the enemy into attacking his camp with full force, leaving the general's camp vulnerable, and then killing the general personally, either disguised as an ally or by stealth.
His introduction showed a character with huge potential, not sure if the author screwed up Kan Ki's character later, but pretty memorable chapter, at least for me.