I'm looking for some inspiration for a fantasy novel with what has a secondary plot going on in the background, which ends up affecting the whole story. This secondary plot is to do with a group of people attempting to create an undead plague while a kingdom is in complete chaos after losing half it's troops and siege vehicles in a war and being forced into a new one as soon as the last one's over. I'm new to the fantasy genre, and would appreciate it if somebody could give examples of novels similar to my own.