Killing the Leviathan

The Killing the Leviathan was an Imperial defensive campaign carried out by the forces of the 180th 'Hornet' Airborne Regiment of the Astra Militarum of the ravenous Tyranids of Hive Fleet Leviathan in defence of the worlds of the Segmentum Tempestus.

Background
During Hive Fleet Leviathan's incursion into Segmentum Tempestus, the Hornets were deployed all over the Segmentum to help ill-fated and ultimately fruitless efforts to help bring down Hive Cities and also evacuate Imperial Citizens ordered to flee by Inquisitor Kryptman. After the horrors witnessed, Lord General Thyme XCI personally requested that Segmentum Command provide any and all knowledge on fighting the Tyranids as possible.