BOOOM BOOOM BOOOM!!!
Each incoming wave of beasts was significantly cut down by devastating calamity-class siege weapons long before they could even enter the geographic vicinity of the Britannian Empire. The surviving majority were intercepted by Martial Artists who were closer to the border but were still far enough to ensure that the immediate devastation of their battle didn't harm the Britannian Empire.
BAM BAM BAM BAM BAM!!!
POW POW POW POW POW!!!
The Martial Artists of the Britannian Empire gritted their teeth as they experienced a battle that was radically different from anything they had ever dealt with in the third Great East Panamic War. Rather than having to deal with independent powerhouse Martial Artists, they had to deal with weaker and more limited beasts and monsters—an endless hoard of them.
It was one Martial Artist for dozens of beasts.