The sword is light and fast, and has the appearange of a broadsword with a large purple vein running up the middle of the blade, with violet runes carved into it and a jewel of amethyst in the pommel. The runes are to show its magical potential, and the gem in the pommel is what strores the magic in the sword.
The sword Elénai was passed down in the Rettensauth family for generations, and likely originally came from Naiakana in the Age of Magic, though Dezzarn Rettensauth, father of Mazzek, had no idea of its magical properties, and did not use them in his time serving in the army.
Mazzek, however, was able to discover and unlock its potential when he was told by a Danethan named Ceiden of Iluvana's Caverns, a long and convoluted system of tunnels beneath Tarethec Bay in Danetha, which lead to the chamber of Lady Iluvana, a sentinel of one of the many Wells of Magic. After passing many trials and defeating the mystical guardians of the caves called Janora, Mazzek spoke with Iluvana and was able to imbue his blade with magic, an act which later aided him in the slaying of several Nai'shanuk, and killing Zethix Dakrannsson.
Though Mazzek Rettensauth should not have been the one to inherit the sword, and instead his brother, Merran Kein Rettensauth, was the one to have it, he was killed in Brimsail and the sword passed instead to Mazzek.
After Mazzek's death at the Battle of Laberan Fields, the sword was taken by Mazzek's lover, Erinah Resoni, to a small village in northern Lareoss, close to the town of Riefarrian. She keeps it there in a small house with her daughter, Rhiane Resoni, for eleven years, until the village is attacked and she, along with Rhiane, is forced to move on. She takes the sword with her, and, at the end of the events in The Starlit King, buries the sword at Laberan, where Mazzek died.