Wild dogs become unusually aggressive because hyenas get too close to puppy dens.
A hyena has been ambushed by African wild dogs while accidentally entering the territory of this pack of dogs, the wild dogs have teamed up to hunt this dangerous foe. In the situation of one-sided fighting, the hyena was completely outclassed.
Another reason feral dogs are so aggressive is thaat hyenas are near the den where the puppies hide and are protected by the pack. Thus, hyenas suffered from the sharp teeth of wild dogs.
The terrible biting force (the wild dog is one of the most powerful carnivores in the animal kingdom) of the wild dog caused severe injuries to the hyena’s hind leg.