Mordin Solus (Mass Effect 3)
Mass Effect 3 was the ending of the classic trilogy, one that was largely about moving from one subplot to the other and tying up all the loose ends before taking the fight back to the Reapers. Of course, one of the biggest loose ends was the Genophage, an artificial disease created by the Salarians in order to stunt the reproductive abilities of the Krogan. Commander Shepard ultimately has to choose to help cure or preserve the disease. Either way, Mordin Solus dies in the process. One of the most likeable characters in the series, Mordin was not only charismatic, but his constant internal tug of war over the Genophage was one of the more compellling story threads.