Jon Connington/Greyscale
Eventually a companion to Young Griff, Jon Connington is a notable character from the books that is absent from the TV show. Oddly, Connington’s death does appear in “Thrones.” The difference is that his deadly disease, Greyscale, instead afflicts Jorah Mormont (as well as Shireen Baratheon, who had it as a child). The disease is generally fatal, but Mormont has magic protection in the form of being necessary to the plot, so he manages to recover.