Firenewt (CR 1)

Medium Monstrous Humanoid (Fire)
Alignment: Usually neutral evil
Initiative: +1 (Dex)

AC: 16 (+1 Dex, +5 chainmail), touch 11, flat-footed 15
Hit Dice: 2d8+2 (11 hp)
Fort +1, Ref +4, Will +3
Speed: 20 ft. (chainmail), base 30 it
Space: 5 ft./5 ft.
Base Attack +2; Grapple +2
Attack: Longsword +2 melee
Full Attack: Longsword +2 melee
Damage: Longsword 1d8
Special Attacks/Actions: Breath weapon
Abilities: Str 10, Dex 13, Con 13, Int 7, Wis 10, Cha 8
Special Qualities: Fire subtype
Feats: Mounted Combat
Skills: Intimidate +2 and Ride +3
Advancement: By character class
Climate/Terrain: Warm mountains
Organization: Solitary, gang (5-10), warband (16-35), tribe (81-100, including 2 clerics of 1st-4th level, 4 elite warriors of 2nd or 3rd level, and an overlord of 4th-6th level)
Treasure/Possessions: Standard

Source: Monster Compendium: Monsters of Faerûn

Breath Weapon (Su): Once every 10 minutes, a firenewt can breathe fire on an opponent within 5 feet. This attack deals 1d6 points of damage; a successful Reflex save (DC 12) reduces the damage by half.

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

Firenewt warriors are typically armored in chainmail and carry longswords, battleaxes, or longspears. Fully 33% of firenewts encountered on the surface ride giant striders trained for melee. At least 90% of elite warriors and all clerics ride these mounts as well.

Fire Subtype

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