The Advance Guard by Don Martinez
Approx. 43,420 words.
Published on February 29, 2012.
Over the course of history, a team of four supernatural agents has been assembled for a Black Ops team unlike any other.Both separately and together, these agents will face down an enemy of immense evil, rising above their differences and individual traumas and coming together to face a demonic matriarch hiding within one of the holiest sites in Europe.