Keen Hearing and Smell. The wolf has advantage on Wisdom (Perception) checks that rely on hearing or smell.
Pack Tactics. The wolf has advantage on an attack roll against a creature if at least one of the wolf's allies is within 5 ft. of the creature and the ally isn't incapacitated.
Snow Camouflage. The wolf has advantage on Dexterity (Stealth) checks made to hide in the snowy terrain.
North Best Friend. The wolf knows what his master wants him to do all time he is no more the 100ft. from him and in eyesight.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: (2d6 + 4) piercing damage. If the target is a creature, it must succeed on a DC 12 Strength saving throw or be knocked prone
Loyal Bodyguard. If someone attacks the wolf's master while he is in 5ft. of him, the wold can use his reaction to attack the attacker.
You might find them walking alone in the arctics, but they are mostly in and near villages (where their master are).