Setting:Brighthammer 40,000/Space Marines (2nd Edition)
Space Marines are the central Defensive/Offensive military force of the Imperium of Man for over 10 milleni. Created by the Emperor of Man himself from his own gene-seed (personal genome) the "Sons of Mankind" or the Primarchs led by the Emperor's favorite son Horus the Space Marines are both a beacon of humanities spiritual and social triumph.
However now the time of endings has begun and while as a ancient wise man once said "Hope for Peace but prepare for War" so now the ranks of the Imperial Marine corps must prepare for the greatest fight possibly within 10,000 years of peace. This is a conflict they may not survive.