The grey talon assassins are a very special group for one reason. They have never been caught. They are impossibly hard to find; many doubt their very existence. Once one has found them, they can be sure the job will be done… for the right price of course.
What if a mage passes his powers on to his firstborn son, and a female mage to her first daughter, leaving the parent POWERLESS? A plain mortal, a sorcerer no longer, all wizardly might gone?
Or: what if a female wizard recieves the power of a mage who sires a child with her? Could lead to promiscuous witches and overly careful mages.