KEEP IN MIND: This information was all gathered from legends you found in books writen by people, not facts given by the DM from his notes so don't assume it all to be 100% factual. This provides a starting point and some points to investigate and look into.

Cirothe is a powerful, magic using, red dragon.
According to legends about Cirothe, she was born to hatred and isolation with her siblings and mother slaughtered. After hatching she made friends with a fiend who she later worked with and made a deal which gave her powerful divine magic which she used to dominate the region, slay rival dragons, and create the Desolation. When she created the Desolation and while doing so she warred with the dwarves and elves, whom she smashed and scattered to the winds. The artifacts from that war supposedly still lay in some areas of the world. The dwarves had an item that would shatter Cirothe's power and the elves held the true name of Cirothe which would grant control over her. Cirothe is hundreds - perhaps even thousands - of years old. She has been in the region for many generations, being here longer than any dwarf or elf. The only two beings that knew a world before Cirothe's existence are supposedly Lorand the Unicorn, the magical guardian of Northbeach Woods, and the Fey Queen who once ruled over the elves in Greyfell Forest. Cirothe is not only an old dragon, which alone makes her fearsome and powerful, but has magic on her side and to top it off it is common knowledge that she has always had minions serving under her: originally kobolds, and now strange new draconic creatures no one has seen before. Many have tried to slay Cirothe, but none have succeeded, including armies of dwarves and elves though it is not impossible, she only needs to be weakened. The legends don't speak of how to weaken her, except that there are ways. Finally, she often enters long slumbers, and awakes to lay eggs and raise wyrmlings every so often. When doing so she has been known to use her minions to capture young virgins as sacrifices to feed her young, demanding nothing less than the most tender of meats. Out of her many rival dragons, there was one that ever posed a threat and nearly destroyed her in a battle. He was a brass dragon named Malentheros which she imprisoned underneath the Deadfall Moors.