Well, seeing as I didn't actually get the chance to torture him and throw him off a building, his actions outweigh mine, so technicqally, I have to make his actions against me justified, by doing them in reverse to him, so that everything returns to neutral status ... so I start by getting someone else to inflict all the wounds I had, on him. Then I throw him ONTO a building from ground level (same building as he threw me off), then I fix all of his torturous injuries (in a painful way). Then, when he is fixed up, we both would have been through the same sort of stuff and we would both be healthy, and therefore, on equal footing ... Then I kill him. (A job is a job, and, as a mercenary, I would have a reputation to protect).