What he looks like:
If you picture one of those strange drummers from Blueman group, combine him with a skeletal Calista Flockhart (Indiana Jones' girlfriend), and then throw some tattered rags around his emaciated shoulders, you'll basically have Raziel. Also, Indiana Jones 4 sucked.
Who he really is:
Most of us know what happens when vampire children start gaining supernatural abilities before their loving vampire fathers: they get beaten. And in Nosgoth, there isn't any sort of child protective services to protect against vampire abuse. As a result, the trounced Raziel enacted a plot of revenge, which entailed killing as many vampires as possible.