Beyond the Crimson Moon: Darkness Rising- Book 2:

After the astonishing events in Under a Crimson Moon, humanity's deepest longings have seemingly been answered with nearly a millennium of peace on Earth after the entity Malek, known as the Darkness, is imprisoned. A time of long lifespans, rejuvenated land, and love without fear is now enjoyed under the rule of the returned ethereal King Elyon. The fugitive-scientist Carn and the reprobate spirits called Legion gather on Mars to launch an all-out rebellion against Elyon and his followers. Renowned bioengineer David Bannister and a priest, Fr. Amos, are sent on a mission by Elyon to Mars to bring Carn to justice. They also must retrieve an artifact of immense power before Legion does which could unravel reality itself. The hopes and fears of all the years will meet as the Darkness rises.