Terminus (Fringe Worlds #1)

Master Sergeant Gant Maker was a highly-decorated and well-respected Marine - until his last mission left him as the sole survivor of an encounter with a vicious race called the Vacra. Served up as a scapegoat and drummed out of the military, he has since lived a life of seclusion with only an adopted alien as a companion. Now the Vacra have returned. As the only person to have ever faced them and survived, Maker is reinstated in the Corps and given the onerous task of finding this enemy on a world located at the edge of known space. Assisting him is an unlikely band of military rejects, including a blind sharpshooter, an unstable psychic, and a genetically-engineered killing machine who refuses to fight. Given that the Vacra have superior weapons and technology, Maker recognizes that his team is at a distinct disadvantage. But Marines are nothing if not resourceful, and Maker has an audacious plan that just may level the playing field - if it doesn't get them all killed.