As Rom Mohc created his Dark Trooper project, another officer stole his plans. This officer redesigned the prototype Dark Trooper, and made the Dark Assault Jet Trooper the basis for "an unstoppable soldier".
They were based off Imperial Dark Troopers to be the next generation of Jet Trooper. Their armor resembled a short blue-gray phase II Dark Trooper, and were armed with either a pistol or blast cannon, and a specialized Arc caster.
Behind the scenes
This was made to retcon Battlefront II's dark trooper.