Bloodmuzzle

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 feet of the creature and the ally isn't incapacitated.

Snow Camouflage. The wolf has advantage on Dexterity (Stealth) checks made to hide in snowy terrain.

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 12 (2d8 + 4) piercing damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked prone.

Cold Breath (Recharge 4–6). The wolf exhales a blast of freezing wind in a 30-foot cone. Each creature in that area must make a DC 14 Dexterity saving throw, taking 20 (4d10) cold damage on a failed save, or half as much damage on a successful one. targets will also have Disadvantage on attack and skill checks till then end of their next turn

3 Legendary resentences:  as a reaction Bloodmuzzle can automatically succeed on any save.

Cunning Action: your quick thinking and agility allow you to move and act quickly. You can take a bonus action on each of your turns in combat. This action can be used only to take the Dash, Disengage, or Hide action.

Terrifying Howl. Bloodmuzzle howls. Any beast or humanoid within 300 feet hostile to Bloodmuzzle and able to hear its howl must succeed on a DC 16 Wisdom saving throw or be frightened for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to any Bloodmuzzle's Terrifying Howl for the next 24 hours. 

Pack Leader. Allies have advantage on an attack roll against a hostile creature if ally is within 30 feet of Bloodmuzzle and he isn't incapacitated. 

Legendary actions: 3 actions per turn. If in Melee Bloodmuzzle can make a bite attack.