Fourth Edition — Rare
Banding (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)
Though many think of Wolves as solitary predators, they are actually extremely social animals. During a hunt they often call to each other, which can be quite unsettling for their prey.