Black dragons in the Empyrean Series are depicted as extraordinarily rare and fascinating creatures with several unique characteristics.

Intelligence and Cunning

Black dragons are described as the smartest and most discerning among dragons. Their cunning nature is so pronounced that it’s said there’s no such thing as outsmarting a black dragon​​.

Rarity

They are the rarest type of dragons, with one character mentioning that there hasn’t been a black dragon born in over a century​​. However, it’s mentioned that two more black dragons hatched in the last year, suggesting a potential increase in their population​​.

Note: In Iron Flame, Tairn mentions that two more black dragons have hatched in the last year, according to Codagh. I have a theory that these two dragons belong to Tairn and Sgaeyl.

Physical Appearance

The scales of black dragons are deeply black. They are unusually large and fearsome. They look menacing. Codagh is the largest dragon on the continent. Tairn is the second largest.

Capabilities and Battle Prowess

Black dragons are revered in battle. Tairn is noted for his significant role in the Tyrrish rebellion, being a middle-aged morningstartail and considered one of the deadliest dragons in Navarre​​.

Original Hatching grounds

One of the original hatching grounds is located in a valley above the Riorson House. This area is noted for its natural thermal energy, which is a critical asset. Notably, this is where dragons from the Dubhmadinn Line, such as Codagh and Tairn, originate​​.

Political Seats within the Empyrean

Currently, as Codagh is the oldest, he is the head of the black dragon den and holds a seat as an elder of the Empyrean. According to Andarna, however, the elders do respect Tairn very much too.

Bonding with Riders and Signets

According to Professor Kaori, the more powerful the dragon, the deeper the bond between dragon and rider. The bonding process between black dragons and their riders appears to be unique and significant.

Tairn was previously bonded with one rider called Naolin. According to Kaori, Tairn almost died when the bond broke, due to Naolin’s losing his life. There are theories speculating that perhaps Tairn himself broke the bond as a result of Naolin potentially turning venin.

This may have caused Tairn to have to break the bond himself to not be affected by the control that venin riders usually exert upon their dragons. (see theory about control and bad smells of dragons here) This in turn might have almost killed Tairn, potentially because severing a bond is life-threatening, or because he was almost executed by the Empyrean for breaking such a sacred rule. Either way, these are just speculations, and we won’t know more before the release of subsequent books in the series.

Bonding with other dragons

Tairn is currently bonded with Sgaeyl. They are deeply connected, but they have not been mated for so long. Once dragons mate for longer periods of time, they can communicate and sense one another from longer distances.