A Big Mistake
Combined with the scary and frantic zombies on the ground and in the air, the Hescos would be forced to aim at these forces.
If they did, then such an attack they prepared would lose its effect. And if they pushed this attack over this force and headed after the retreating main bulk of my ground army, they might get more disappointed.
The retreating forces were running mad like their lives depended on it. And that wasn't an exaggeration. I estimated for them to reach the safe place of the central region before the arrival of that scary shield over the leftover forces.
If I was Hescos, I'd have to accept such a loss. The attack was enough to wipe out my entire forces out there, and would have cost me a lot if it went through.
Luckily the response of the two generals was fast enough to save the day.
Seeing their prey escape, the slowly approaching defensive shield suddenly shook and accelerated like a bolt of lightning.