Parental abandonment forced Andi Tolen to fend for herself from early childhood, and she claimed to have first killed a sentient, albeit accidentally, when she was only twelve, as a result of an altercation with a man who caught her in the act of theft. In her struggle to flee, she grabbed his blaster and reflexively fired, felling him. This tragic encounter imprinted upon a young Tolen a grim "kill or be killed" worldview that would come to define her through adolescence and into adulthood. While using her extensive autodidactic survivalist knowledge to earn a living through guide and exploration work (supplemented with petty theft), she also began to lure wealthy offworld customers into robberies by local Tatooinian gangs in exchange for a cut.
These first steps into organized crime eventually brought Tolen into the employ of Huttese crimelord Herogga as a messenger and errand girl. Herogga appreciated Tolen's cleverness and ability to consistently accomplish difficult tasks, such as tracking those who wanted to remain hidden through the wilderness outside Tatooine's spaceports. Tolen developed a reputation first as the Hutt's best tracker, and after developing herself as a fighter, as one of his best bounty hunters, as well.
Some time after rising to the top of Herogga's ranks, Tolen left her homeworld and turned to freelance, accepting occasional assignments from her first employer out of a vague loyalty and a desire to remain in the Hutt's good graces, but mainly hiring herself and her ship, the Desert Rat, out to those offering the best pay, or else pursuing lucrative bounties on her own initiative. She was often underestimated because of her youthful face which belied a coldly calculating steeliness. Though Tolen prided her skill in collecting targets alive, she also didn't shy away from killing if necessary. Of her work, she tersely remarked, "It's nothing personal. If I show up looking for you, it's because you did something to bring me there."
Tolen's difficult life made her averse to trusting in and depending on others, and she was devoted to chasing her prey alone, hiring or cooperating with others only when she deemed it necessary, but beneath this fierce individualism lay a deep loneliness. Though harsh circumstances forged Tolen into an aloof and hardened woman, she secretly longed for friends or even friendly acquaintances instead of a life filled only with targets and potential targets, employers, and fellow bounty hunters who could be comrades one day and rivals the next.