Giant, Sun (CR 12)

Huge Giant (Fire)
Alignment: Usually neutral
Initiative: +2 (Dex); Senses: darkvision 60 ft., Listen +19, and Spot +19

AC: 20 (-2 size, +2 Dex, +10 natural), touch 10, flat-footed 18
Hit Dice: 13d8+91 (149 hp)
Fort +15, Ref +6, Will +8
Speed: 40 ft.
Space: 15 ft./15 ft.
Base Attack +9; Grapple +30
Attack: Gargantuan longspear +20 melee, or +10 ranged
Full Attack: Gargantuan longspear +20/+15 melee, or +10 ranged
Damage: Gargantuan longspear 2d8+19/x3, rock 2d8+13
Special Attacks/Actions: Rock throwing, spell-like abilities
Abilities: Str 37, Dex 14, Con 25, Int 15, Wis 18, Cha 14
Special Qualities: fire subtype, rock catch
Feats: Alertness; Combat Casting; Mounted Combat; Point Blank Shot; Precise Shot
Skills: Handle Animal +15, Hide +11*, Listen +19, Ride +16, and Spot +19
Advancement: By character class
Climate/Terrain: Warm and temperate deserts
Organization: Solitary, pair, gang (3-5), or family (3-8 plus 1-4 noncombatants plus 1 4th-6th level adept, cleric, or sorcerer)
Treasure: Standard

Source: Monster Manual II

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.