The Sith Trooper is a very agile and mobile unit. Already being faster than most units the "combat rush" ability allows him to move almost as fast as the Droideka unit.
His weapon is similar to the TL-50 in the way that both weapons also have an alternate fire. Compared to the TL-50, the Quarrel Blast deals more damage and travels in a straight line. It can almost one-shot three of the four default trooper classes, and can be used to finish off a weakened unit if they are weak enough.
With the Oppression Grenade, you can be sure to hold off heroes a lot better! A powerful weapon that is able to block the health regeneration of an enemy, depending on your situation, this can be deadly to enemy heroes and special units, who have more health than regular infantry.
With the Combat Rush ability, you are able to traverse the battlefront at a speedy rate, while regening your health faster than normal. Watch out, runaways!
The Sith Trooper's Seeker Tactics ability reveals enemy units in the area of the trooper, the number of units expanding for every kill, allowing for a recon of enemy movements and positions and the ability to ambush.
Although Sith troopers were canonically affiliated with the First Order, Sith troopers were actually soldiers raised by a secret cult of Sith loyalists and followers of Emperor Palpatine, the Sith Eternal, and were the soldiers of the Final Order.