When the archers were almost out of arrows, and the magicians were almost out of magic power, William and Est immediately ordered for the next teams to take their place.
The archers who had run out of arrows, immediately went to the rear to restock on ammunition, while the magicians retreated in order to drink potions to replenish their magic power. William and Est made several teams to alternate between attack and retreat because they knew that they couldn't afford to exhaust all their manpower through continuous fighting.
The only problem was the Spirit Division. The Head Prefect and the Vice-Prefect were inexperienced in large-scale battles and pooled all of their fighting power together. They didn't think about forming teams to alternate between attack and recovery because they thought that they could wipe out the enemies with their superior fire power.