Angels Sanguine
One of the second founding successor chapters of the Blood Angels, the Angels Sanguine has a long and proud history in the Imperium, stretching back ten thousand years to the time of the Great Crusade. Indeed the original Angel Sanguine were part of the Blood Angels Legion at the time, forming the new chapter when the Legion split down into thousand man chapters.
Like most successor chapters they don't have much fluff written about them, GW leaving the door open on that so players can make their own history. Whether this will happen or not is unknown since they have a difficult colour scheme (dividing one half red, one half black) so unless you have a steady hand and want a challenge you will most likely choose an easier chapter to paint.
What is known about them in the fluff is that they never take their helmets off in public or even to other Space Marines, even from the Blood Angels. If they do forgo their armour, they wear deep hoods to obscure their faces. This has led to a number of rumours about them and what goes on in their chapter-monastery, which has some pretty deep catacombs it seems.....
Really some /tg/ write them up some good fanfiction please? Lets have a new blood quest featuring all of the Blood Angel successor chapters!