Murdering low-level tribes was indeed very easy. Given Du You's current magic power, he could wipe out countless Beastman gathering points in a single day. As long as they were discovered by him, there was no need for them to exist anymore.
With the spread of the poison, followed by fire, the camps of the Half-Beastmen and the Boarmen would be burned to ashes. There would be nothing left to tell of their existence, not even their corpses or food supplies.
Even if a limited number of corpses did remain, they would quickly become food for other creatures, being left out in the open. No matter how many he slaughtered, there would always be a shortage of food for the Beastmen.
The Beastmen, who were already dealing with a food crisis, now experienced even more internal chaos.
Many Beastmen began hoarding food in secret, which led to a burgeoning food crisis in their city. The price of food on the market soared while the quantities dwindled.