Dragon, Chromium, Very old (CR 20)

Huge Dragon (Cold)
Alignment: Always Lawful Evil
Initiative: +0; Senses: blindsense 60 ft., darkvision120 ft., low-light vision, and keen senses

AC: 34 (-2 size, +26 natural), touch 8, flat-footed 34
Hit Dice: 28d12+140 (322 hp); DR: 15/magic
Fort +23, Ref +17, Will +22
Speed: 40 ft., fly 150 ft. (poor), swim 60 ft.
Space: 20 ft./10 ft.
Base Attack +30; Grapple +50
Attack: 1 bite +40, 2 claws +35, 2 wings +35, 1 tail slap +35, 1 crush +35
Damage: 1 bite 2d6+12, 2 claws 1d8+6, 2 wings 1d6, 1 tail slap 1d8, 1 crush -
Special Attacks/Actions: Breath weapon 16d8 (31)
Abilities: Str 35, Dex 10, Con 23, Int 20, Wis 21, Cha 20
Special Qualities: Immunity to cold, vulnerability to fire, Pass without trace, Ice shape, Wall of ice CL 13th, SR 26, Fear aura (DC 30)
Feats: #Feats: 10
Class Skills: Appraise, Bluff, Skill points: 156, and and Jump
Advancement: 29-30 HD (Huge)
Climate/Terrain: Any cold mountain or underground
Organization: Solitary (1 dragon, any age), clutch (1d4+1 wyrmlings, very young, young, juvenile, or young adults), family (pair of mature adults and 1d4+1 offspring)
Treasure/Possessions: Triple Standard

Source: Dragon #356

Breath Weapon (Su): A chromium dragon has two types of breath weapon, a line of solid ice (cold) and a cone of freezing crystals. Creatures within a cone of freezing crystals take 1 point of Dexterity damage per age category of the dragon (Fortitude half).

Spell-Like Abilities: 3/day - pass without trace (ice and snow only); 2/day - ice shape (as stone shape, but applies to ice instead of stone), wall of ice.

Skills: Appraise, Bluff, and Jump are considered class skills for chromium dragons.

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.