Adamantine dragon

Adamantine dragons, also called adamantite dragons, were one of the mightiest species of planar dragon. They were native to the Twin Paradises of Bytopia.

Description
Adamantine dragons had a typical draconic build, but their bodies were relatively small in proportion to their claws, wings, and tail. They ranged in size from wyrmlings to  great wyrms. Adamantine dragons were born with their scales- which looked like silvery metal covered in diamond dust- fully developed. It was said that the light that reflected from their scales in brilliant beams and scintillating rainbows was refreshing to those who could bask in goodness, but painful to the evil. On the head, horns swept back and formed a radiant, crownlike crest.

Personality
Adamantine dragons were sometimes considered exemplars of good, for they were helpful to a fault and willing to sacrifice what was needed for the common good of intelligent creatures. They were also eternally vigilant protectors of their native plane.

Abilities
Adamantine dragons, naturally, had the wide variety of magical abilities one would expect from such a powerful dragon species. Their natural weaponry was adamantine-like, if not actually adamantine, in nature, and they dealt out more damage than was proportionate to their size. Their were also skilled at destroying equipment such as armor or weapons, which they favored over outright killing enemies. They were not injured by either fire or nonmagical weapons.

Adamantite dragons possessed two breathe weapons: one was consistently described as a line or cone of white-hot fire up to long, while the other was variously described as a cone of time-stopping gas of the same dimensions, which could only be used on their native plane, or as a cone of gas that induced a hold monster-like effect, which had no such restriction on location—perhaps indicating that it was the same breathe weapon, but one that was, uniquely, more powerful on their native plane than on other planes.

Adamantine dragons also had a few innate spell-like abilities that they gained as they grew older: while still very young, they could replicate mirror image; when juvenile, they could replicate dimension door; when adult, they gained dispel evil; when old, banishment; all of these they could use thrice each day. Once each day, they could replicate: antipathy, when old; when ancient, power word, stun; when a great wyrm, reverse gravity. Some reports also spoke of them using magic missile or blink as adults.

They could also take a humanoid or animal form, akin to the polymorph self spell, though the change did not heal them. They could maintain this alternate form until they choose to return to their true form.

Combat
Adamantine dragons disliked phsyical combat but would nonetheless use their adamantine-like claws to destroy equipment- or slay truly evil creatures without mercy. They typically opened combat by using their hold monster-like breathe weapon.

Society
Adamantite dragons were the self-appointed guardians of Bytopia, where they constantly patrolled the plane to guard against invading fiends or spying rilmani, among other unwanted intruders; their duties to Bytopia meant that they almost never visited other planes. Most adamantine dragons lived near the towns of the gnome petitioners, who built their mighty allies magnificent castles for their lairs. More occasionally, an adamantine dragon would lair in wild Shurrock instead, to better watch over travellers there.

Adamantine dragons did not, however, have any moral objections to hunting nonsaptient lifeforms for food, and they could be great hunters with large appetites.

Trivia
Adamantine dragons were among the planar creatures known to respond to the elven High Magic summoning spell celestial army.