Winter Wolf (CR 5)

Large Magical Beast (Cold)
Alignment: Usually neutral evil
Initiative: +5 (+1 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., low-light vision, scent, Listen +6, and Spot +6

AC: 15 (-1 size, +1 Dex, +5 natural), touch 10, flat-footed 14
Hit Dice: 6d10+18 (51 hp)
Fort +8, Ref +6, Will +3
Speed: 50 ft.
Space: 10 ft./5 ft.
Base Attack +6; Grapple +14
Attack: Bite +9 melee
Full Attack: Bite +9 melee
Damage: Bite 1d8+6 plus 1d6 cold
Special Attacks/Actions: Breath weapon, freezing bite, trip
Abilities: Str 18, Dex 13, Con 16, Int 9, Wis 13, Cha 10
Special Qualities: cold immunity, fire vulnerability
Feats: Alertness; Improved Initiative; Track
Skills: Hide -1*, Listen +6, Move Silently +7, Spot +6, and Survival +1*
Advancement: 7-9 HD (Large); 10-18 HD (Huge)
Climate/Terrain: Cold forest
Organization: Solitary, pair, or pack (2-5)
Treasure/Possessions: 1/10 coins; 50% goods; 50% items

Source: Monster Manual

Breath Weapon (Su): Cone of cold, 15 ft., every 1d4 rounds; damage 4d6, Reflex half DC 16. Winter wolves can use their breath weapon while biting.

Trip (Ex): A winter wolf that hits with a bite attack can attempt to trip the opponent as a free action without making a touch attack or provoking an attack of opportunity. If the attempt fails, the opponent cannot react to trip the winter wolf.

Cold Subtype: Cold immunity; double damage from fire except on a successful save.

Skills: Winter wolves receive a +1 racial bonus to Listen, Move Silently, and Spot checks, and a +2 racial bonus to Hide checks. Their natural coloration grants winter wolves a +7 racial bonus to Hide checks in areas of snow and ice. A winter wolf has a +4 racial bonus to Survival checks when tracking by scent.

Winter wolves typically hunt in packs. Their size, cunning, and formidable breath weapon allow them to hunt and kill creatures much larger than themselves. A pack usually circles an opponent, each wolf attacking in turn to exhaust it. If they're in a hurry, white wolves try to pin their foes.

Cold Subtype

A creature with the cold subtype has immunity to cold. It has vulnerability to fire, which means it takes half again as much (+50%) damage as normal from fire, regardless of whether a saving throw is allowed, or if the save is a success or failure.