User blog comment:Suparockr/List of Plotholes throughout the series/@comment-3325589-20120717070525/@comment-4953843-20120717072943

read the wiki's entries for the merc groups. those backstory snafus have already been dealt with.

as for the blood pack composition and leadership confusion, think of it that most merc groups are organized into cells. a vorcha being "a" leader of the blood pack in me3 doesn't necessarily mean that he's "the" supreme overlord for the blood pack in general. it also helps to know how their particularly violent lifestyles (+ giant squid abominations invading the galaxy) offer a high probability of personnel replacement every so often, from grunts to bosses.