In one of the adventures my gaming group encountered while I was GMing a game of Fate Core Star Wars, the crew crash-landed on a wasteland planet that happened to be a testing ground for prototype assassin droids. These are the droids they ran up against while trying to find a way off of the planet.
IG-107, the Hunter. A stealth assassin droid with reactive camo and heat vision. The crew ran into this droid in the jungle where they crashed. They repurposed the sensors from the ship's wreckage to triangulate his position and took him out with a single blaster shot through his rifle's scope, exploding his head.
T8-G8, the Falconer. This high-speed, quadrupedal droid controls a flock of Vulture drones. The crew encountered this droid while racing across a blasted wasteland on speeder bikes. They had a high speed chase down an old highway, which ended when one of the crew blew up an upcoming overpass, dropping a pile of rusted-out landspeeders onto the droid.
X0-FT1, the Bantha. A heavily armoured droid with massive firepower. The crew encountered this droid inside the ruined city core. After the last fight, they had repurposed the centaur droid into a remotely-controlled, walking bomb. After taking out the Bantha droid's shield generator, they piloted the explosive droid right into the Bantha and detonated it. The mangled droid managed to escape and hasn't been seen since.
2-D6, the Twinja. This two-headed close-quarters-combat droid is able to split itself into two separate fighters. The crew was attacked by this droid while they were in the archive stacks deep under the city. They pushed a giant stack of computers onto one half of the droid and then blasted the other with the rifle they looted from IG-107.
Q6-4V, the Judge. Originally designed as a legal droid, 4V's advanced brain was shoved into an assassin droid chassis and loaded up with combat software. After having its targets designated, his logical mind quickly came to the conclusion that the most efficient solution to eliminating all of its targets would be to first eliminate those who designated the targets in the first place, his Imperial handlers. When the crew encountered him in the Imperial outpost at the center of the city, he was surrounded by the bodies of a dozen Imperial officers and stormtroopers. After a tense standoff in which the assassin blew up the only ship off of the planet and nearly convinced the crew's own droid to turn on the rest of the party, they managed to incapacitate him; however, after deciding they had a common enemy, the crew let the droid go.