9. Aurra Sing
Tatooine is one of the most vibrant worlds in Star Wars, teeming with life (read: scum and villainy) from across the galaxy. George Lucas and the other fine minds behind 1977's Star Wars made that abundantly clear when Luke Skywalker entered Mos Eisley for the first time, and everything that made the locale charming in that initial encounter was present and accounted for in the first Star Wars prequel: The Phantom Menace.
Many of Star Wars' most creative aliens can be spotted during one of the film's best set-pieces - the Boonta Eve podrace. There are the brilliant co-commentators, Fode and Beed (the former voiced by Whose Line is it Anyway? alum Greg Proops), Orr'UrRuuR'R (the lead Tusken who takes potshots at the racers), and then Aurra Sing, a mysterious pale-skinned alien who viewers can spot in the foreground as the racers make their way through a canyon.
Sing's design instantly caught the attention of fans, and it wasn't until long she found herself the focus of several expanded universe stories. The old Legends continuity established that she was a former Jedi Padawan who became a bounty hunter, but that was changed once again when the character made her animated debut in the 2008 Clone Wars animated series.
This time she was just a feared bounty hunter, but she was also instrumental in training Boba Fett after the death of his father Jango, and even assisted Boba in trying to assassinate Mace Windu in revenge. She dies by the time of the events of Solo: A Star Wars Story, but it's still unclear just how exactly she met her end.