Kahn's command activated the King of the Dead skill which let him create subordinates without even having to touch them.
After an upgrade in his Rank, this ability also had an increase in its range and now he could directly create subordinates within one kilometer radius from him.
There were over 600 bodies from both sides and the majority consisted of Master Rank fighters from different classes.
Kahn waited for the exact reason for each sides to kill themselves off first so he could easily kill the remaining people even through he didn't have any enmity with Demi-Human faction people. Plus saving Szayel would help him for the long term in his opinion.
Although most of them were beginners at best, still the variety of different classes gave Kahn a big boost in the number of strong subordinates. He would've never found these many master-rank corpses together in the same place at Flavot city.