A double-bladed spinning lightsaber was utilized by Tualon Yaluna during his time as a member of the Inquisitorius.
The weapon featured a ringed emitter which could partially detach from the remaining hilt, allowing both blades to rotate rapidly without effort from the wielder. For a Jedi hunter like an Inquisitor, this function likely served as a way to intimidate opponents, as well as deflect any form of direct attack. However, this was also the weapon's primary weakness, as a lightsaber-wielding opponent could simply separate the emitter itself and cut the weapon in half, as was demonstrated by Kanan Jarrus during his final duel with the Grand Inquisitor aboard the Sovereign.
Darth Vader kills Tualon Yaluna with his own weapon.
After the Jedi Knight Tualon Yaluna was captured by the newly formed Galactic Empire and turned to the dark side of the Force, he was given a new lightsaber, which he used during training duels with fellow Inquisitor Iskat Akaris and their master, the Sith Lord Darth Vader. During his time as an Inquisitor, Yaluna carried the weapon during a number of assignments, including a mission to Firrhana and the hunt for Eeth Koth. His last use of the lightsaber was in combat against Darth Vader, who eventually used the Force to kill Yaluna with the weapon.
Concept art of Tualon Yaluna and his Inquisitor lightsaber.
Giuseppe Camuncoli's concept art for Yaluna's Inquisitor lightsaber was initially in the form of standard split saber, but soon took the form of the double-bladed spinning lightsaber typically used by Inquisitors, as seen in its official depictions.