Although there are good Lord of the Rings based RTS titles that could easily be placed on this list, Middle Earth: Shadow of Mordor was not only fun, but innovative in design that allowed for players capture forts and defeat rival loud-mouthed Orc generals.
Although some could say that Warner Brothers is getting a bit too repetitive with this gameplay design, such as in the recent Mad Max, it does not make this game any less addictive.
I have to capture each fort, defeat each general, and pick up every flippin' herb that appears along the path. Warner Brothers has developed great gameplay mechanics that completely appease my OCD.
Image source: Crave Online