Dragon, Brown Wyrm (CR 23)

Colossal Dragon (Earth)
Alignment: Usually neutral evil
Initiative: +0; Senses: blindsense 60 ft., darkvision120 ft., low-light vision, keen senses, and tremorsense 500 ft.
Languages: Draconic

AC: 35 (-8 size, +33 natural), touch 2, flat-footed 35
Hit Dice: 36d12+360 (594 hp); DR: 20/magic
Fort +30, Ref +20, Will +26
Speed: 60 ft., burrow 60 ft.
Space: 30 ft./20 ft. (30 ft. with bite)
Base Attack +36; Grapple +68
Attack: 1 Bite +44, 2 claws +39, 2 wings +39, 1 Tail Slap +39, 1 crush +39, 1 Tail sweep +39 melee; Breath +44 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 22d6 (38)
Special Attacks/Actions: Breath Weapon, fear (DC 34), SR 32
Abilities: Str 43, Dex 10, Con 31, Int 22, Wis 23, Cha 22
Special Qualities: Acid immunity, create water, sandstorm, summon Huge Air elemental, summon greater air elemental as 15th-level caster
Feats: #Feats: 13
Class Skills: Climb, Hide, Skill points: 222, and Survival
Advancement: 37-38 HD (Gargantuan)
Climate/Terrain: Any desert
Organization: Solitary, pair, or family (1-2 and 2-5 offspring)
Treasure/Possessions: Double Standard

Source: Monster Compendium: Monsters of Faerûn

Breath Weapon (Su): The brown dragon's breath weapon is a line of acid. It does not use this attack against mounted foes, since it knows that horses are good eating. Using a breath weapon is a standard action. Once a dragon breathes, it can't breathe again until 1d4 rounds later. A blast from a breath weapon always starts at the dragon's mouth and extends in a direction of the dragon's choice.

Tremorsense (Ex): Brown dragons can automatically sense the location of anything within 500 feet that is in contact with the ground.

Create Water (Sp): The dragon can use this spell-like ability once per day.

Sandstorm (Sp): Once per day, an adult brown dragon can create a vortex of violently churning sand at a distance up to 80 yards away. All creatures within a 60-foot radius of the center of the sandstorm take 1d6 points of damage each round they remain within the sandstorm. Characters in the swirling sands are blinded and must make a Balance check (DC 15) during each round they move more than 5 feet or fall prone.

Summon Huge Air Elemental (Sp): Once per day, an old brown dragon can cast summon nature's ally VI to summon one Huge air elemental, 1d3 Large air elementals, or 1d4+1 air elementals of smaller size.

Summon Greater Air Elemental (Sp): Once per day, an ancient brown dragon can cast summon nature's ally VIII to summon one greater air elemental, 1d3 Huge air elementals, or 1d4+1 air elementals of smaller size.

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 330 feet are subject to the effect if they have fewer HD than the dragon (36).

A potentially affected creature that succeeds at a Will save (DC 34) 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.

Earth Subtype

This subtype usually is used for elementals and outsiders with a connection to the Elemental Plane of Earth. Earth creatures usually have burrow speeds, and most earth creatures can burrow through solid rock.