Tang Dynasty: Starting with 3,000 elite cavalry, a bloody battle to retake the city.

Han Ye travels back in time to the Wude era of the Tang Dynasty.
Just as the city fell, the Turkic cavalry massacred its inhabitants.
Fortunately, the system was activated in time, summoning three thousand elite cavalry at the start of the battle to retake the city.
When reinforcements arrived, they discovered that the city had already been recaptured by a mysterious figure…