Celestial Fury

Celestial Fury was a powerful, +3 sentient katana from from the island of Wa, in Kara-Tur. Although the blade was originally designed to slay a powerful and mysterious dragon, it ended up housing its spirit and maintaining its sentience. It possessed a number of inherent and spell-like effects, centered around storms and lightning.

Description
A blade of immaculate craftsmanship, Celestial Fury was an extremely flexible, yet completely unbreakable weapon that was constantly honed to razor sharpness. It's hilt was wrapped in leather, granting it a comfortable grip adorned with a magnificently large pearl. The Wa-an characters for "celestial fury" were inscribed on the blade, which shone a pale violet hue and snapped with electricity. The katana's sheathe was made from the hide of a gray dragon and momentarily flashed in hues of silver, blue and violet.

Powers
The katana only allowed it self to be wielded by chaotic-aligned individuals, shocking anyone else who attempted to wield its power. To those it deemed worthy, the sword granted immunity to all forms of electricity, granted them flight for up to four hours per day, and protected them from wetness due to adverse weather or other elemental forces.

Upon drawing the blade, its scabbard generated a 2-mile (3.2 km) storm centered upon the blade, causing a flash of lightning and rumble of thunder that could inflict both temporary blindness and deafness in all but the wielder. The wielder would also generate a two mile radius of inclement weather centered on themselves, regardless of local weather conditions. Upon landing a blow, the blade would boom thunder again, though not quite as loud as when it was drawn, and could stun any opponents of its wielder.

Three times per day, a landed blow from Celestial Fury could shock its victim, and, once per day, could evoke a lightning bolt, as per the spell.

Sentience
The dragon's sentience within the katana was a particularly chaotic one. It desired its wielder to display exhibitions of their power and enjoyed its ability to cause bad weather. Beyond this, Celestial Fury as a weapon desired vengeance against the descendants of Daimyo Hoshi and the smith Chigatta, those responsible for its death, and loss of freedom, as a dragon. Despite its immense will, the spirit of the dragon could only communication in the form of vague empathy.

History
The province of a Waan daimyo, Hoshi Katahiroi, was suffering under unnatural and destructive weather. A dragon of a type never encountered before was found to be the cause - it was dubbed Celestial Fury. Hoshi wished the dragon dead to spare his province more devastation. In his lands resided a reclusive weaponsmith named Chigatta who was also known to be a master of the mystic arts. Hoshi commissioned Chigatta to forge for him a weapon that could destroy Celestial Fury's spirit as well as its body.

Chigatta created a katana, sharing the magical beast's name, more fine than Hoshi could've imagined. The sword was imbued with the power of flight and so Hoshi took to the skies to slay the dragon. Above the stormclouds, roars echoed along with a man's shouts and fire lit up the night skies for several days until Hoshi returned to the ground claiming a victory of law over chaos since the dragon's spirit was now trapped inside his sword. Hoshi then asked Chigatta to craft a scabbard next, ornamented with a magical pearl that was in the dragon's possession.

Unfortunately, while Hoshi was a great warrior, he was weak of will and the dragon's spirit possessed Hoshi's body, forcing him to kill first Chigatta, then himself. The blade disappeared shortly afterward.

Apearance in Faerûn
In the late 14 century DR, Celestial Fury was in the possession of a slaver named Koshi, who frequented a guarded compound within the temple district of Athkatla. He and his group were defeated by Gorion's Ward and their companions.