I've heard the name but wasn't very familiar with her backstory. But according to Wookiepedia, she was an assassin under Palpatine but went rogue after his death and then became full-on goody two shoes Jedi Master and Luke's wife? Was she ever an actual Sith force user or just a high level lackey?
Here's some notes I wrote out years ago.
Mara Jade Skywalker – (Legends only) Born 17 BBY, died 40 ABY – Was taken from her parents to be a servant to Palpatine where she began training in the force. She got top notch & very specialized training to be an agent of the empire & by the age of 14 became an “Emperor’s Hand”… ie one of Palpatine’s personal "assassin/problem solvers". The Emperor's Hands had authority over almost everyone, to the point they could take over a Star Destroyer... but they operated in secret for the most part. Even the other hands didn't know about each other.
During the years following 0 BBY she spied on Vader & delivered reports to the Emporer. Jade felt the division of Vader regarding Luke & hoped that he would betray the emperor so that she could slay him & take his place as the Emporer’s apprentice. Many missionz were carried out by her & even one where a common enemy was taken down with the assistance of Luke Skywalker… though Luke had to escape afterward to avoid being hunted himself!
She waz later a spy in the guise of a dancing girl… in Jabba’s palace when Luke came to rescue Han, but her plan got cut short when she tried to use the force on Jabba & he sent her away with a promise to never return. Luke had a force vision years later that if she would’ve been present the whole time, that she would’ve prevented his escape. The emperor was aware that Vader & Luke would kill him & his last command to her was the task of Killing Luke.
When Sid died, her hatred for Skywalker burned deeper as she went rogue & undercover… resourcez & priviledge now gone… she did what she could to make money & survive… all the while her force powers slowly dwindling. She eventually got herself into a smuggler’s roll… drifting from different jobs under different aliases… 6 ABY – 9 ABY.
Her allies caught Luke while his x-wing fighter was broke down while in space. They took him back to their base in an attempt to collect a bounty that was on his head… but he escaped & Jade made chase. They ended up needing each other to survive & while Jade was clear that she intended to kill Luke… they agreed to work together in order to get out of the mess they found themselves in. Eventually rescued by Han & Lando after they were clear of danger, Luke took off while Jade stayed.
Another shared adventure later between the 2 resulted in Luke recognizing the Emperor’s command in Jade’s head that kept her hate boiling against him. He explained it to her & vowed to help her be relieved of it. 9 ABY – 19 ABY… After some work with the subliminal messages Palpatine had put in her head… Jade eventually fully renounced the dark side of the force.
19 ABY fell in love with Luke & married him, became a Jedi Master under “the New Jedi Order.” Birthed son “Ben” in 26.5 ABY & took neice Jaina Solo as an apprentice through knighthood. She became “chief of State” of the “Galactic Federation of Free Alliances” & Served on the Jedi Council. She convinced many people to switch from dark influences to light, but was ultimately killed by her darkened nephew Jacen Solo. (<--- Jacen is basically Kylo Ren's story)