Marcus was originally 12th level. at this point i don't know how far he's leveled.
I think the average Shadow is around 4th level (2 levels ranger 2 levels of Cleric, fighter or rogue).
AA leads and trains the Shadows, Marcus runs the day to day.
The "Strikers" which are essentially Shadow archer specialists had Point Blank Shot, Presise Shot, Track, Endurance, Favored Enemy; Dragons, Wild Empathy and Combat Style(Rapid Shot).
The other special units are the "Blades" (melee/unarmed combat specialists), "Menders" (medics) and "Markers" (Trapfinders and removers). Only the "Markers" have ranged weapons feats (Point Blank Shot).
Hope that helps.