Blood Claws are very new Space Wolves. While most chapters have their newbies start out in the scouts, to learn the various skills they will need as full marines, the Space Wolves are unable to restrain their recruits enough to make them quiet, and so they lump them in great packs of howling warriors. To simulate this wanton madness, I left the blood claws with no helmets, and tried to pick the 'younger' looking heads. (Namely, heads without epic beards, and with the wilder haircuts.)
Also, because of their wilder nature, as much as possible I tried to depict them running, charging, swinging, etc.
I may do a second picture spread of the blood claws, if I can find more good images. Next time (hopefully not as delayed...) will be the long fangs!