L8-L9 was a prototype battle droid built by TaggeCo during the Clone Wars. The droid was created in the utmost secrecy, and was part of a ploy by Baron Orman Tagge to gain favor in the sight of Palpatine.
To test the L8-L9, Orman Tagge arranged the droid to fight in the Rattatak arenas to show off its abilities. Unfortunately for L8-L9 and Tagge, Dark Jedi Asajj Ventress bested the robot, therefore shutting down any further production of the combat droid L8-L9 was based on.
However, the legacy of the project lived on through the Z-X3 experimental droid trooper, also worked on by TaggeCo. Eventually, while both products failed, they led to the famed Dark trooper project.
The Z-X3 experimental droid trooper was a prototype battle droid created by Tagge Company during the era of the Galactic Civil War. Designed to function in environments too hazardous for organic stormtroopers, the Z-X3 was the brainchild of Imperial officer Rom Mohc, who was inspired by his experiences facing Confederate battle droids during the Clone Wars. However, the Empire rejected the droid troopers, leaving the few Z-X3 units that were produced to either find remote Imperial service or fall into private ownership.