Asperi (CR 3)

Large Magical Beast (Air and Cold)
Alignment: Always neutral
Initiative: +3 (Dex); Senses: true seeing, Listen +6, and Spot +7
Languages: Telepathy 100 ft.

AC: 16 (-1 size, +3 Dex, +4 natural), touch 12, flat-footed 13
Hit Dice: 4d10+12 (34 hp)
Fort +7, Ref +6, Will +5
Speed: 60 ft., fly 120 ft. (average)
Space: 10 ft./5 ft.
Base Attack +4; Grapple +12
Attack: Hoof +7 melee
Full Attack: 2 hooves +7 melee and bite +2 melee
Damage: Hoof 1d6+4, bite 1d3+2
Special Attacks/Actions:
Abilities: Str 18, Dex 16, Con 16, Int 15, Wis 15, Cha 15
Special Qualities: feather fall, ride the wind, immunities, cold subtype
Feats: Alertness; Flyby Attack
Skills: Intimidate +7, Listen +6, Spot +7, and Survival +8
Advancement: 5-12 HD (Large)
Climate/Terrain: Cold and temperate mountains
Organization: Solitary or herd (2-4)
Treasure/Possessions: None

Source: Monster Manual II

True Seeing (Su): An asperii can continuously see things as they are with a range of 120 feet. This functions as the true seeing spell; it can be dispelled, but the asperii can restart it again on its next turn as a free action.

Feather Fall (Su): Four times per day, an asperii can use feather fall on itself or a creature it touches. This functions as the spell cast by an 8th-level sorcerer.

Ride the Wind (Su): Asperii are able to ride air currents of natural or magical nature. This allows an asperii to add 5 feet to its fly speed for each mile per hour of wind over 20.

Immunities (Ex): Asperii are immune to all gaze attacks.

Cold Subtype (Ex): Cold immunity, double damage from fire, except on a successful save.

Telepathy (Su): Asperiis can communicate telepathically with any creature within 100 feet that has a language.

Skills: Asperiis receive a +4 racial bonus to Listen, Search, and Spot checks.

They are gentle beings and avoid combat, but if pressed, they are quite capable of defending themselves. Asperiis attack with their hooves and bite.

The Asperii first appeared in Dragon #89 (in the original "Creature Catalog" section) as the Wind Steed. It later appeared in MC3, and MC annual 4.

Air Subtype

This subtype usually is used for elementals and outsiders with a connection to the Elemental Plane Air. Air creatures always have fly speeds and usually have perfect maneuverability (see the section on Movement).

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.