Mornelithe Falconsbane was the use-name of the final incarnation of Ma'ar. 'Mornelithe' is actually a Kaled'a'in word meaning 'one who returns,' with the connotation of returning multiple times through the ages for revenge. 'Falcolnsbane' was obviously chosen as a statement on his feelings towards the Tayledras and all they hold dear.
He was a ruthless blood-path Adept who lived during the reign of Queen Selenay. Falconsbane began this incarnation by taking over the body of a young Shin'a'in, his descendant: An'desha. He took over when An'desha ran away from the plains to find refuge amongst the Tayledras, but got lost along the way. Young An'desha attempted a fire spell, which was the way Ma'ar recognized that one of his descendants was worthy of his possession, and so he rushed in.
During this life, Falconsbane altered his own body to have more catlike features and a perverse sexual nature. He first tested these alterations on the body of his daughter, Nyara. For his own form, he combined the features of man and lynx, giving himself tawny gold hair, fanged canine teeth, and gold-green slit-pupilled eyes.
Falconsbane enslaved and broke Starblade, elder of k'Sheyna Vale and father of Darkwind k'Sheyna. He forced Starblade to crack the k'Sheyna heartstone in an effort to steal its power for himself. This corrupted the heartstone and caused the deaths of many k'Sheyna mages, as well as polluting the vale.
Falconsbane was thrice defeated by the combined efforts of Elspeth, Skif, Darkwind, Firesong, Nyara, Need, Hydona, Treyvan, Tre'valen, and Dawnfire. The first time, he teleported at the last moment and spent weeks regaining his power before returning to his lair. The second time, he was cast into the Void when Nyara struck his makeshift heartstone.
Falconsbane was pulled from the Void by a faulty Gate spell cast by King Ancar of Hardorn, where he was enslaved and forced to help Ancar with his attacks on Valdemar. Here, An'desha was able to get a bit of control back for his body, and was helped by Tre'valen and Dawnfire, now Avatars of the Shin'a'in Goddess, to search through Falconsbane's memories.
Falconsbane was defeated the final time when he was run through with the sword Need by his daughter Nyara. When his spirit fled the body to await a new incarnation, he was chased into the Void by Firesong and destroyed completely--although it is believed the gods may see fit to return him to the world in the physical form of a slug or something of that nature.
The Shin'a'in Goddess granted An'desha his body back and returned both his features and his calendar age, leaving him only with the striking slit-pupiled cat-eyes as a reminder of Falconsbane.