If it's not too, late, I would be interested in this game, too. It's been a while since I last played a low-level tactic game
I was thinking along the lines of a 29 years old human rogue4/wizard1. He is actually a foreigner, as he established in the city 3 or 4 years ago. He comes from a country somewhere to the north (sadly, I don't know the setting very well...), and he is a little bit melancholic about the great frozen wastes.
He originally came here to the city with his lover (a priestess of Skaia, the nephew of his mentor, who adopted and converted him into their faith, as he was previously just the child of some barbarians worshiping their wild barbarian deity, regarded as a mere pagan cult).
However his relationship with the priestess of Skaia had an ugly end when she failed in romantic love with a handsome paladin, firstborn of one of the most important nobles in the city. Let's say that our hero didn't enjoy that too much, but eventually he swallowed it down. As for now, he works as an assassin. Even if he is a true neutral, he is on the borderline with good and chaotic, in the sense that he almost never accepts jobs involving the killing of someone innocent (like caring priests who are trying to defend the local population from the criminals). However, there are not only ethics involved in this decision: he thinks himself a killer, not a local thug.
As a son of barbarians, and later the adept of men living on the borders of civilization, he has learned to change, adapt and survive in almost any situation. He has a fierce sense of independence and a great will to win against whoever opposes him. Thus, he never surrenders even when all seems lost.
He retains something from his barbarian heritage, because he views almost all of the inhabitants of the civilized land as weak: they don't have to fight each days against the cold, the wild predators and the other savage tribes, so they have grown complacent. It is no surprise that he overall is quicker, more intelligent and more resilient than most of them.
Thanks to his maxed ranks in disguise, a nice set of masks and some illusion, he managed to keep his identity secret. He lives as Ethranor a son of some distant and rich merchant, who enjoys parties and women (especially the former

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As a son of a rich merchant, and thanks to his natural social skills, he managed to get known among the rich, and he is often invited to parties. Well, most of them think him a nice and absolutely non-dangerous fellow. Hah.
He relies on his social and stealth skills to scout the location, gather information about the defenses of the place and make some cunning plan. He strives to make his engagements as elegant as possible: his ideal assassination is when they discover that the target is death when he is already back home after retiring the rest of his compensation. It has happened only twice this far, though.
Recently, he put aside his training in stealth and worked as an apprentice to a lone wizard, in order to gain some flexibility and magical skill: he thinks that the ability to use scrolls is valuable. He will not pursue this path, however, and will soon turn back to the ways of the true assassin.