Soul Redemption - Soul Collector Series, #6

When the world's greatest ghost hunter sets out for revenge, there's going to be hell to pay.Retired Marine, Shane Ryan, knows all about war. He's fought in the toughest hellholes on the planet, and he has the scars, both physical and mental, to prove it. As the world's foremost ghost hunter, Shane has defeated supernatural evil beyond imagination. But this time, the fight is personal. After battling his way through the wilderness and defeating an army of bloodthirsty wraiths, Shane is finally at the enemy's door.
Constantine Agios, an insane occultist, has innocent blood on his hands. And Shane is going to make him pay for every last drop. Pitting his mastery of the dead against Constantine's arcane powers, Shane launches a brutal one-man crusade against this supernatural killer. When the dust settles, only one will be left standing. But in this paranormal war, the stakes are higher than Shane could possibly imagine.
And victory comes at a terrible cost.