A Horus Heresy novel

As Horus deploys his forces, a small band of loyal Space Marines from disparate Legions learn that a massive enemy armada is heading to Ultramar, home of the Ultramarines, headed by the most destructive starship ever constructed.

READ IT BECAUSE
A group of heroes who know there is no glory for them come together to strike a blow against the traitors. It's a classic tale of a a handful of brave warriors against a mighty foe, and it doesn't get much mightier than the Furious Abyss...