Saerelyon is known to have grown larger than Vhalax, the dragon of Aeganar IV during his reign. His scales are as black as coal, and his eyes are a fiery orange much alike his rider. His claws are remarkably sharp, and his teeth are easily the length of longswords. His wingspan could cast a shadow over a small village, much like his ancient forefather Gavarex, albeit his ancestor was profoundly larger. According to dragon lore, some puportedly written by Aenarion himself, dragons continue to grow if their health is maintained well -- and Saerelyon was indeed well taken care of.
Saerelyon was given to Taeronys during his infancy as an egg. After two weeks of placing the egg with young Taeronys in his cradle, the egg hatched. As a hatchling, he was about the size of a child and at first glance about the same size as Taeronys at the time. Queen Hylaera, Taeronys's mother, would typically worry about him getting hurt and had a nervous disposition when her son played with the hatchling. Saerelyon at one point accidentally burned Taeronys's finger which resulted in a permanent scar but it did not hurt their relationship.
Taeronys and Saerelyon grew together over the years and since acquired a near-unbreakable bond. Saerelyon grew abnormally large despite being a mere 8 years of age. He was as large as a carriage and had to be taught and fed more vigorously than before. Saerelyon grew used to sleeping at the end of the bed with Taeronys but could no longer fit in the chambers. Taeronys had aspirations of riding his dragon and made this quite clear to both of his parents. His father Aeganar encouraged the idea whereas his mother was wary of it. Requests were made for a saddle capable for use on a dragon, saddlers based their designs on what Draegon had brought overseas centuries ago. Many prototypes were made and tested due to the fact that the most efficient saddle designs for dragonriding were lost in Drakonia. Eventually, a proper saddle was made and at 8 years of age, Taeronys began to ride his dragon, taking off from the old roosting towers and soaring above the Dragonspire, making it a habit to mark all landmarks of note that he could see from his aerial perch. Taeronys grew infatuated with the feeling and the adrenaline that came with the feeling and would begin to train himself and Saerelyon on how to cooperate with each other while in flight.
When Taeronys was given his own land to govern, he ordered dragon roosting towers to be built to accommodate Saerelyon. Much later during the Siege of Dragonspire, Saerelyon destroyed siege weaponry like cheaply-built toys and burned thousands of men alive in their armor, set out as if they were roasting. Through the course of the siege, Saerelyon was wounded and seperated from his rider when Taeronys was forced to escape Dragonspire before being overrun and risk being killed. Only Vhalax's body was recovered after the siege, so the possibility of Saerelyon's survival is quite likely. Citizens have reported sightings of a large black dragon ever since, on both continents. Roars can also be heard that are much deeper and guttural than other dragons, and several scholars have pointed similarities to roars of grief.