@FallenTrinity*ding ding ding* Correct answer!!
Dragonlord Ojutai. XD
@RaiWas thinking about something like a dragon more focused on magic and knowledge.
Its scales are not nearly as hard as the other dragons, its horns are made of bone (normal density) and it is overall a less lot "tough and tanky" than normal dragons (also a lot more light and agile on the sky).
To compensate for those big weaknesses, it was born with a great magical affinity, using spells to enhance its breath, fight and etc.
Basically it would be very different from other dragons regarding her personality. Instead of having a lair, it lives on a colossal library built by herself, where she dedicates her time to study both magic and technology.
A very important ally of the Magoi, its library would be the place where the magoi visited to research and learn with the dragon and its incredible amount of books and scrolls.