Hive Fleet Leviathan didn’t come in from the galactic east like the hive fleets before it. It slipped in under the galactic plane and pushed up from the south, and that route is what made it the worst Tyranid threat the Imperium has faced.
How Leviathan’s route differed from earlier fleets
Most hive fleets hit the Imperium from the Eastern Fringe. Leviathan went around. It skirted beneath the galactic rim and then rose up through the plane of the galaxy, which caught the Imperium completely off guard.
From there it spread across a huge front: Ultima Segmentum, Segmentum Tempestus, and eventually even Segmentum Solar. That’s the heart of the Imperium, and Leviathan got close enough to scare it.
The twin tendrils and the Shadow in the Warp
Leviathan’s signature move was splitting its attack into two enormous tendrils, hundreds of light years apart. That gap wasn’t a weakness. It was the plan.
The distance let Leviathan stretch the Shadow in the Warp across everything in between. Worlds caught in that gap couldn’t reach the Imperium by astropath, and Imperial reinforcements couldn’t navigate the Warp to reach them. They were cut off and eaten.
- First contact lost in late 997.M41, in Segmentum Tempestus
- Inquisitor Kryptman’s census mapped the silent worlds into a pattern of a single vast fleet
- One main tendril was aimed straight at Terra
Tarsis Ultra and the cordon
That tendril heading for Terra was finally stopped at Tarsis Ultra. It was a real victory, but a local one. Leviathan as a whole kept coming.
The Imperium answered with the Galactic Cordon, a defensive line built on the worlds Leviathan had already stripped. It was meant to contain the fleet. It didn’t.
Baal, the Great Rift, and the fourth Tyrannic War
When the Great Rift tore the galaxy open, a large part of Leviathan got cut off while it was making its main push on Baal, the Blood Angels’ homeworld. Most of that force died in the fighting there, against the Blood Angels’ defenders, the Indomitus Crusade, and daemons that showed up mid-battle.
Leviathan wasn’t finished, though. In M42 it launched a fresh offensive with several new tendrils into Segmentum Pacificus, putting Segmentum Solar under threat again and kicking off what’s known as the Fourth Tyrannic War.
Key facts
- Leviathan attacked in 997.M41, entering from below the galactic plane rather than the Eastern Fringe
- It spread across Ultima Segmentum, Segmentum Tempestus, and into Segmentum Solar
- Its twin-tendril formation stretched the Shadow in the Warp, cutting off whole regions from the Imperium
- One tendril, aimed at Terra, was halted at Tarsis Ultra
- Most of the fleet was destroyed at Baal during the Blackness, but Leviathan survived
- In M42 it opened a new offensive into Segmentum Pacificus, starting the Fourth Tyrannic War
FAQ
Where did Hive Fleet Leviathan attack from?
From below the galactic plane. It came in under the galactic rim and pushed up through the southern part of the galaxy, rather than arriving from the Eastern Fringe like earlier hive fleets.
Why were Leviathan’s two tendrils so dangerous?
The tendrils were hundreds of light years apart on purpose. The gap let Leviathan spread the Shadow in the Warp over a huge area, cutting off psychic communication and Warp travel for every world caught between them.
Was Hive Fleet Leviathan ever defeated?
No. One tendril was stopped at Tarsis Ultra, and most of the force that attacked Baal was destroyed, but the fleet as a whole survived and launched a new offensive in M42.