Whenever you get a kill you get a force back, plus if Inquisitor then you get another and then if the kill was against a force user then another one, if it was a bounty hunter you get another one, and if the killer was Jango against primary or secondary then you get another back. You can get 3 force back in a single turn if you spend 1 to do a payday and get a kill, plus a bonus 1 force if it was against a force user.