Stupid on both sides. The attacking force should have just launched fire arrows into all the tents and let them burn then cut down the stragglers and reinforcements. As was already mentioned, Shi Wanshui was an idiot for being lax in his guard with a known enemy 10km away and where was the MID spy net of Shanhai?
Isn’t Sha guy in mc’s alliance now? If not, who tf is the other county that joined apart from mc’s gf? And apart from that. I’m disappointed with this Emperor’s level historic figure. Or more like, disappointed by the author for creating a high level character only to end up useless for that level.