IG-71

Nicknames: Seven (preferred), Lucky Seven, Lucky, Cheat, Three-arms, Clanker.
Gender: Masculine programming
Species: Illegally modified IG-Series Assassin Droid
Construction Date: 20 BBY
Home: Galma / Black Spire Outpost, Batuu
Occupation: Bounty Hunter / Droid Fighter / Resistance Agent?
Known Modifications: Destroyer Droid arm mounted on shoulder, substantially modified personality chip, enhanced and reprogrammed combat instincts, stolen lightsaber for unconventional use.
" Pride: I shoot these because I can, I have this lightsaber because I can. I can assure your destruction because I can. "
~IG-71 "Seven", at encroaching First Order stormtroopers.
IG-71 is a heavily modified assassin droid built for droid fighting in the lawless, tech-savvy town of Galma. While most of the new features aren't visible, the most stark modification is the Droideka arm mounted on his shoulder, used for sustained, oppressive fire on key targets while the base arms do the rest. He also appears to carry around a stolen, contraband lightsaber.
Background
IG-71, sometimes collequially known as Seven, was a champion droid fighter in the shady town of Galma on the backwater planet Batuu. Originally a factory default IG assassin droid, he was extensively modified by his anonymous, gambling owner to win more fights, such as utilizing a droideka arm on the shoulder, and merging combat subroutines from salvaged commando droids and tactical droids to quickly determine every possible outcome of a battle on the spot, and determine the best course of action. The sheer amount of victories Seven would achieve would lead to Assassin Droids (and possibly Battle Droids) to be banned from droid fighting arenas in Galma and Black Spire Outpost.
With no longer a source of income, the desperate owner of Seven sells the assassin droid to one of the leading crime bosses of Black Spire, named Oga, in exchange, the owner would have the proper credits to leave town and planet, as there were already some other droid fighting competitors that wanted him dead. IG-71 stayed on Batuu, secretly programmed with self-preservation instincts and a hinge of self-awareness. IG-71 would become a bounty hunter under Oga's ownership, taking in assassination contracts and sometimes odd jobs to rake back to his newfound boss, but sometimes keeping credits for himself for repairs and upgrades at the neighboring Droid Depot.
After the reaches of the conflict between the Resistance and the First Order moved into Black Spire, IG-71 would enact as a pseudo-agent of the Resistance in an effort to keep his contraband existence in tact, also ordered by Oga to eliminate and dispose of any First Order troop that knows too much of the illegal happenings being performed. Also during this time, the Milennium Falcon is docked in Docking Bay 5, to be used by Hondo Ohnaka for smuggling valuable coaxium for the Resistance and possibly others who may need it. During a routine investigation and check for any snooping First Order troops inside the Falcon, IG-71 finds himself in an in-depth talk with the central computer of the Falcon, a talk that would further Seven's own self-awareness, and has fully realized his individuality, though will still do his job because as he describes; "It's a pleasurable meatbag concept called 'fun'."
At some point, for the act of furthering capabilities, IG-71 stole a green kyber crystal lightsaber from a secret lightsaber workshop acting as a salvage company as a front.

"That freakin' tin can has a lightsaber!"
~An unfortunate thug
Personality
IG-71, or Seven by his preference, can be cold, calculated, and will see it through that his job will get done, no matter the cost, like most IG units. However, Seven hosts instincts of self-preservation, and is capable of friendship in the means he sees someone useful in the long run, although, Seven mostly befriends droids, more often because he finds them relatable. Due to his extensively modified combat routines, Seven is also extremely athletic, precise, and outright violent. Often not caring about the belongings of others, he may take them if he sees personal use for it.
Seven also possesses some ability of rhetort, and isn't afraid to insult anyone be they friend or foe, likely as a leftover competitive subroutine from his droid fighter days, and oddly enough, will sometimes state the type of sentence prior to speaking it, much like the HK series of assassin droids. As a means to stand out and show his individuality, he wears a green scarf around his neck.
Equipment
DLT-20A Blaster Rifle
E-11 Blaster Rifle
NT-242
S-5 Heavy Blaster Pistols
Droideka Blaster Cannon
Stolen, Reforged Lightsaber
Disclaimer
I don't own Star Wars, all rights belong to Lucasfilm and Disney. Any images used here are used under the Fair Use Act, any and all information here should be regarded as fan fiction.