Though wolves are capable of killing animals ten times their weight, some species of their prey have adapted effective means of defeating wolf attacks. The muskox is a formidable creature, strong and well equipped to defend itself against attack. The animals possess sharp hooves and curved horns. When they are under attack, they position themselves in a defensive formation that is nearly impossible to breach. Even a small group of muskox makes a significant adversary, so there is little chance for an attacker that attempts a head-on confrontation.
Less harm can come to the wolf pack if the members stick together.
The wolves strategy is straightforward. First they test the herd by making the muskox run. This will enable the wolves to discern if there are any injured, slow, or weak individuals among them. Even a minor injury may be enough to tip the scales in the wolves' favor, so they study the herd carefully. This is neither the first, nor the last time these adversaries will face each other.