Shadow Guard

The Emperor's Shadow Guard was an organization of elite, Force-sensitive soldiers recruited from the defeated remnants of the Sun Guard and Jedi Knight's who fell to the Dark Side of the Force. They served the Galactic Empire during the Great Jedi Purge. They were trained by Darth Vader.

 Shadow Guards In The Shadow Empire 

It wasn't until Dark Lord of the Sith Onepath Rainwar rebuilt the Imperial Royal Guard Academy on Yinchorr that the Shadow Guard's were reborn and brought into the new Shadow Empire. Trained masterfully by the Dark Lord Onepath Rainwar himself, they were enforced with a complete lightsaber or two and a blaster rifle.

The Dark Lord Onepath Rainwar wanted his Shadow Guard's to have elite training from the Shadow Army and the Sith Order. As they would usually succeed in the Sith Academy since they were exiled Jedi Knight's from the Jedi Order, they would, however, lack in military training. The elite Shadow Guard's would be tested on Yinchorr and if they passed the Dark Lord's wrath and fury, they would be allowed to be on the battlefield.

Since they would be more elite in primarily everything needed, Sith Training and military training, they would be the last ones to go on the battlefield if there was an urgency at war. More skillful in lightsaber training and in using the Force, they would primarily be better at being a Sith Knight and a Shadowtrooper. With their elite training, some were replaced as instructors in the Sith Academy's throughout the galaxy, making sure every Sith Acolyte would achieve their goals in becoming a Sith Knight.