Dragon, Silver Great Wyrm (CR 25)

Colossal Dragon (Air)
Alignment: Always Lawful Good
Initiative: +0; Senses: blindsense 60 ft., darkvision120 ft., low-light vision, and keen senses
Languages: Draconic

AC: 41 (-8 size, +39 natural), touch 2, flat-footed 41
Hit Dice: 40d12+400 (660 hp); DR: 20/magic
Fort +32, Ref +22, Will +32
Speed: 40 ft., fly 200 ft. (clumsy)
Space: 30 ft./20 ft. (30 ft. with bite)
Base Attack +40; Grapple +72
Attack: 1 Bite +48, 2 claws +43, 2 wings +43, 1 Tail Slap +43, 1 crush +43, 1 Tail sweep +43 melee; Breath +48 ranged
Damage: 1 bite 4d8+16, 2 claws 4d6+8, 2 wings 2d8+8, 1 tail slap 4d6+24, 1 crush 4d8+24, 1 tail sweep 2d8+24, Breath weapon 24d8 (39)
Special Attacks/Actions: Breath Weapon, fear (DC 40), SR 32
Abilities: Str 43, Dex 10, Con 31, Int 30, Wis 31, Cha 30
Special Qualities: Reverse gravity, Control weather, Control winds, Fog cloud, Feather fall, Cold and acid immunity, cloud-walking, polymorph self, CL 19. Can also cast cleric spells and those from the Air, Good, Law, and Sun domains as arcane spells.
Feats: #Feats: 14
Skills: Skill points: 406 and plus Jump 40
Advancement: 41+ HD (Colossal)
Climate/Terrain: Temperate and warm mountains and underground
Organization: Solitary, pair, or family (1-2 and 2-5 offspring)
Treasure/Possessions: Double Standard

Source: Monster Manual

Alternate Form(Su): A silver dragon can assume any animal or humanoid form of Medium size or smaller as a standard action three times per day. A dragon can remain in its animal or humanoid form until it wishes to assume a new one or return to its natural form. A true seeing spell or ability reveals the creature's natural form. A creature using alternate form reverts to its natural form when killed, but separated body parts retain their shape. A creature cannot use alternate form to take the form of a creature with a template.

Breath Weapon (Su): A silver dragon has two types of breath weapon, a cone of cold (24d8 damage, Reflex save for half DC 39) or a cone of paralyzing gas. Creatures within the latter must succeed at a Fortitude save (DC 39) or be paralyzed for 1d6 rounds plus 12 rounds. Using a breath weapon is a standard action. Once a dragon breathes, it can't breathe again until 1d4 rounds later. If the dragon has more than one type of breath weapon, it still can breathe only once every 1d4 rounds. A blast from a breath weapon always starts at the dragon's mouth and extends in a direction of the dragon's choice.

Cloudwalking (Su): The dragon can tread on clouds or fog as though ground. The ability functions continuously but can be negated or resumed at will.

Frightful Presence (Ex): A young adult or older dragon can unsettle foes with its mere presence. The ability takes effect automatically whenever the dragon attacks, charges, or flies overhead. Creatures within a radius of 360 feet are subject to the effect if they have fewer HD than the dragon (40).

A potentially affected creature that succeeds at a Will save (DC 40) remains immune to that dragon's frightful presence for one day. On a failure, creatures with 4 or fewer HD become panicked for 4d6 rounds and those with 5 or more HD become shaken for 4d6 rounds.

Dragons ignore the frightful presence of other dragons.

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).