You were moved back to back from missions, it was some time after the battle of Panisia where your attention was shifted to an assassination attempt. Something that the Emperor himself instructed you to investigate and destroy. It wouldn't take long before you realized Ochi Beston was partly behind the attack.

Ochi had joined the Crimson Dawn, betrayed Sidious, but you decide against killing him as you could use him to your advantage in the hunt for the syndicate, keeping this deduction as a secret.

While investigation into the deaths from the assassination of the Emperor's Royal Guard, they were all killed by the assassin Ochi as part of Crimson Dawn leader Lady Qi'ra's grand plan to destroy the Sith.

The Knights of Ren of all thieves believing it was a brilliant idea to raid Fortress Vader on Mustafar. Hired by the Crimson Dawn to attack the Fortress, they were brazen enough to attack Lord Vader directly, in Sidious's words. As if these fools believing they'd be able to do damage against the Sith at all was nothing but amusing. They do not understand the true power of the dark side, just merely pretenders.

They approached the fortress from the south, evading Imperial sensors with signal jammers, and entered through an unguarded entrance, entering inside the Sith cave beneath the fortress. The Knights successfully reached the vault and collected the Screaming Key, but their heist triggered an alarm, leading to a battle with the lava trooper garrison.

They were successful in striking down many of the troopers with their assortment of primitive melee weapons, while Ren, wielded his red lightsaber, which originally owned by his predecessor.

They all felt a new dark presence arrive at the Fortress. It was here they realized they had to double time their escape efforts.

You have arrived to deal with these pathetic rabble.