The Battle of Macragge

When the first tendrils of Hive Fleet Behemoth fell upon Ultramar, the Imperium had no name for the devouring swarm. The Battle of Macragge would give it one, written in the blood of a Chapter and the ashes of a world. The Tyranids descended upon the fortress-world in numbers beyond counting, a living storm of chitin and hunger that blotted out the stars and stripped the outer worlds of every scrap of biomass.

The Space Marines of Macragge fought as few had ever fought. Guilliman's sons held the polar fortresses against endless assault, and in orbit the Ultramarines fleet burned itself to cinders to break the Hive Fleet's spine. Marneus Calgar himself led the defence of the northern bastion, losing his hands and nearly his life as swarming horrors overran the walls. Every metre was purchased with lives beyond reckoning.

Salvation came only when the Imperial Navy's Battlefleet Ultima translated in-system and unleashed apocalyptic fury upon the fleet-mind. The synaptic web collapsed, and the leaderless swarm dissolved into feral madness. Macragge endured, but the First Company was annihilated to the last, and the wider galaxy learned that a new and insatiable terror had crossed the void from the darkness between galaxies. It would not be the last time the swarm came hungering.