A skirmish took place in 18 BBY aboard the Imperial Lambda-class T-4a shuttle ST 321. While aboard the shuttle headed back from Yinchorr to Coruscant, Emperor Palpatine and Darth Vader were attacked by traitorous Emperor's Hand Sheyvan and six clones of Dark Jedi Sa Cuis. They took control of the ship and Vader, along with Lieutenant Erv Lekauf and his clones, were forced to engage the Dark Jedi in combat.
Armed with flamethrowers, the Lekauf clones burned four Cuis clones; the remaining two were Force choked by Vader. Sheyvan fought Vader alone in a brief duel and attempted to turn Vader against Palpatine, but was ultimately killed. Afterward, the Sa Cuis template was decommissioned, although the Emperor remained open to the possibility of cloning a Force-sensitive army in the future.
Lekauf, however, was burned during the battle. Vader tended to Lekauf, which was a contributing factor to Lekauf's immense respect for the Dark Lord, which he later transmitted to his grandson, Jori Lekauf. Jori would later reference the injuries his grandfather suffered during the battle.
- The Essential Reader's Companion