Dragon, Adamantine Great Wyrm (CR 24)
Colossal Dragon (Extraplanar)
Alignment: Always neutral good
Initiative: +0; Senses: blindsense 60 ft., darkvision120 ft., low-light vision, and keen senses
Languages: Celestial, Draconic, and Gnome
AC: 43 (-8 size, +41 natural), touch 2, flat-footed 43
Hit Dice: 42d12+462 (735 hp); DR: 20/magic and 10/adamantine
Fort +34, Ref +23, Will +31
Speed: 60 ft., fly 250 ft. (good), swim 40 ft.
Space: 80 ft./15 ft.
Base Attack +42; Grapple +77
Attack: 1 bite +51, 2 claws +46, 2 wings +46, 1 tail slap +46, 1 crush +46, 1 tail sweep +46
Damage: 1 bite 4d8+19, 2 claws 4d6+9, 2 wings 2d8
Special Attacks/Actions: Breath weapon 24d8 (42)
Abilities: Str 49, Dex 10, Con 33, Int 24, Wis 27, Cha 24
Special Qualities: Immunity to fire, adamantine touch, increased damage, Improved Sunder, mirror image, Dimension door, Alternate form, dispel evil, Banishment, Power word stun, Reverse gravity, SR 36, Fear aura (DC 42)
Feats: #Feats: 15
Skills: Skill points: 300
Advancement: 43+ HD (Colossal)
Climate/Terrain: Any land and underground (Twin Paradises of Bytopia)
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 #321
Breath Weapon (Su): An adamantine dragon has two types of breath weapon, a line of searing white hot fire and a cone of hold monster gas. Living creatures within a cone of hold monster gas must succeed on a Will save or be held, regardless of HD, for 1d6 rounds plus round per age category of the dragon. This is a mind-affecting compulsion enchantment effect.
Increased Damage (Ex): Because of their oversized limbs and weapons, adamantine dragons deal damage as if they were one size category larger than they really are. The adamantine dragon doesn't gain the additional attacks of the larger size, only greater damage.
Adamantine Touch (Ex): An adamantine dragon's natural weapons are treated as adamantine weapons for the purpose of overcoming damage reduction and bypassing hardness.
Improved Sunder: An adamantine dragon has the Improved Sunder feat as a bonus feat, and it frequently attempts to destroy its opponents' weapons and armor.
Alternate Form (Su): An adult or older adamantine dragon can assume any animal or humanoid form of Medium or smaller as a standard action three times per day. This ability functions as the polymorph spell cast by a 10th-level caster, except that the dragon does not regain hit points for changing form and can only assume the form of an animal or humanoid. The dragon can remain in its animal or humanoid form until it chooses to assume a new one or return to its natural form.
Spell-like Abilities: 3/day - mirror image, dimension door, dispel evil, banishment; 1/day - antipathy, power word stun, reverse gravity.
Skills: Heal and Tumble are considered class skills for adamantine dragons.
Extraplanar Subtype
A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.
Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.