Siege of Cthonia
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This article is about the Horus Heresy battle; for the Rulebook, see Campaigns of the Age of Darkness: The Siege of Cthonia. |
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The Siege of Cthonia began in 006.M31 during the Horus Heresy, as several Sons of Horus splinter fleets attempted to break the Imperial Fists' blockade of their Homeworld, Cthonia.[1][2]
History
Cthonia been blockaded by the Imperial Fists since the Heresy in 006.M31,[2] as given the situation elsewhere in the Galaxy the world was too powerful to fully conquer. To do so, would have required the Imperium to commit substantial strength, that was needed to fight Warmaster Horus' forces elsewhere. However, as the Warmaster approached the Sol System,[1] several Sons of Horus splinter fleets attempted to break the blockade, most notably a relief force (dubbed the "True Sons of Cthonia") under Captain Vheren Ashurhaddon, who destroyed many loyalist ships in orbit before reinforcing the planet with a large fleet that outnumbered the loyalists 3-to-1.[3e][3b]
The Imperial Fists under Lord Castellan Evander Garrius launched a desperate counterattack to prevent the freeing of Cthonia. If they did so, then the Warmaster's assault on Terra, would be reinforced with thousands of new Sons of Horus Legionaries.[1][3a] As the conflict dragged on, the Imperial Fists besiegers began to recruit new Space Marines from Cthonia, resulting in the ironic situation that by the later stages of the siege many Imperial Fists were natives whereas the Sons of Horus relief troops had been recruited from other planets and were foreigners.[3a]
The siege's main phase began in 012.M31,[1] and became focused around the Traitor's Gate (formerly known as Lupercal's Gate) Hive of the world. Cthonia's vast subterranean networks and gang culture made the fighting grueling and brutal, with repeated attacks by both sides often achieving little. The Imperial Fists found themselves trapped between the Sons of Horus both above and below, causing their advance to falter.[3a] Besides their Astartes warriors, the Sons of Horus employed unaugmented Human chain gangs as well as newly inducted hastily produced Initiates as cannon fodder.[3c] To try and break the stalemate, Ashurhaddon used Chieftain Kovarny's Heathens Reaver Attack Squad to kill Garrius, who was located within the Traitor's Gate. His death would then topple the Imperium's resistance and allow the Sons of Horus to finally advance their invasion into the Hive. However due to fighting together during the Great Crusade, Kovarny considered Garrius to be his Brother and instead secretly sought to save the Imperial Fist by converting him to the Traitor's cause. Garrius would refuse to do so, though, and ultimately killed Kovarny before his remaining forces escaped from the Chieftain's pursuing Reaver Squad.[3e]
After several years of bloody stalemate, a Dreadwing force of the Dark Angels arrived shortly after the end of the Siege of Terra. By then, the Imperial Fists positions on Cthonia seemed to have been heavily reduced, but the Dark Angels commander Annael decided to quickly set off Vortex Bombs on Cthonia rather than waste the element of surprise to warn them to evacuate. The Dreadwing launched a shock assault on Cthonia in order to set the Vortex Bomb, but Brother Karael disobeyed orders to warn the Fists to evacuate, causing a vicious Sons of Horus counterattack to fall on their position as a result. The Dark Angels and Fists both took heavy casualties, but some forces managed to evacuate as the vortex bomb detonated and shattered Cthonia in half.[3d]
Order of battle
Imperial
- Imperial Fists
- Dark Angels (final phase)[3d]
- Shattered Legion warbands[4]
- Loyalist Thousand Sons cadre[4]
- Loyalist Imperialis Armada[3e][3b]
- Loyalist Imperial Army
- Loyalist Cthonian gangs[3c][3f]
Traitor
- Sons of Horus
- Local garrison[1]
- Relief forces (True Sons of Cthonia)[4]
- Word Bearers elements[3e][3f]
- Alpha Legion elements[4]
- Dark Mechanicum
- Traitor Imperial Army[3c]
- Traitor Imperialis Armada[3e][3b]
- Traitor Cthonian gangs[3c][3f]
Sources
- 1: White Dwarf 470, pg. 105 - Chronicles of the Horus Heresy
- 2: Horusheresy.com galactic timeline (last accessed 2/6/2022)
- 3: Cthonia's Reckoning (Anthology)
- 4: Warhammer Community: Decide the Fate of Cthonia With the First Horus Heresy Campaign Book (Posted on 22/03/2023) (Last accessed on 22/03/2023)