Doom of Esophon Prime

The Doom of Esophon Prime was an Imperial defensive campaign conducted by the Warmachines Space Marine Chapter and local Adeptus Mechanicus forces in the vain attempt to save the doomed forge world of Esophon Prime from the encroaching Tryanid hordes of Hive Fleet Behemoth.

History
The Warmachines move to protect the Forge World of Esophon Prime, the vital forge world in the direct path of the encroaching fleets of Hive Fleet Behemoth. The Marines were under no illusion that they cannot hope to hold off the xenos threat forever, and urge the Mechanicus priests to evacuate with as much precious archeotech and STC Machines as possible. The Mechanicus, after calculating the chances of victory in this field, acquiesce and begin the preparations for evacuation. The Hive Fleet, perhaps sensing its fleeing biomass, appears and strikes with the speed of a coiled viper, and takes both the Marines and The Mechanicus on the back foot. As they hastily entrench a defensive perimeter and battle line, the ships in orbit frantically move to avoid the massive Hive ships from swallowing them whole.

Reinforced by Skitarri and Adeptus Mechanicus forces, the Marines of the War Machines enact a fighting retreat as the unrelenting and unending tide of xenos pushes them slowly, but steadily back. The primary forges and manufactory complexes of the planet alert the marines that the most vital and rare pieces of Machinery have been successfully relocated to both the Mechanicum and Warmachine ships, but it is far too late to enact any sort of escape to Orbit. As the jaws of the hive fleet close around Esophon Prime, The Skitarri commanders and Adeptus Mechanicus tech-priests volunteer to hold back the tide alone, allowing the Space Marines to escape, before detonating a series of planetary nuclear warheads and destroying the planet. Initially reluctant to retreat in the face of their foes, the Mechanicus commanders argue that the Warmachines are more valuable, and less expendable, than their Skitarri battle-brothers, and that the Warmachines will be needed on more warzones to hold back the tide of the Imperium's enemies.

Relenting to the sound reasoning, The Warmachines return to orbit as the Skitarri take the full brunt of the Tyranid assault. They last a matter of hours before being crushed under the unending horde of Shrieking, chittering horrors. Within moments of the Skitarri line collapsing, a series of sub-tectonic nuclear warheads ignite, fracturing the planet, and burning its occupiers alive in a sea of red hot magma, dealing a grievous blow to the Tyranids present, and leaving them unable to recover, let alone gain more Biomass. The Mechanicus priests and their precious technology is relocated to Volgenstraad's moon, an already booming Forge World that bolsters under the newcomers arrival. In return for their assistance, the Warmachines are granted access to many of the Mechanicus' ancient technologies, and the in return for the Skitarris sacrifice, the Warmachines repaint the inner roundel of their chapter symbol red in honour of the Mechanicus soldiers' courage.