You know the basics behind the Horsemen. Death, Pestilance, War, and Famine will ride forth upon the world when the seven seals holding them at bay are broken. In the world of Helldiver, these seals are protected by an ancient order from the Vatican. Each one is protected by a soldier. The story focuses on Adam Cahill, a descendant of the bloodline of Solomon, who is called into action to help protect the seals at all costs from the Nicolaitans. And costs there are. Saving mankind is not something that you can just do. It takes sacrifice and even though Cahill has dedicated his life to the cause, that's still not enough.