Caustic Blades

The Caustic Blades are one of the original Space Marine Legions created near the end of the Unification Wars. The 15th Legion, originally named the Umbral Brothers, were one of the smallest Legions of Space Marines, having barely 25,000 Marines by the Triumph of Ullanor. This is due to their extremely volatile geneseed mutation which caused the Betchers Gland of the Caustic Blades to be extremely over active. Due to their small numbers, they originally served mainly alongside the War Talons Legion, however they quickly began serving alone after the founding of the 19th Primarch, Khamilla Ra'akkad.

Once the 15th's Primarch, Venun Falkas, returned, he quickly began changing the Legion to suit his needs. Where they were once reconnaissance focused, they now specialised in sabotage, utilising the Primarchs new technology. Though Venun Falkas began as an exceptional leader, as the Betchers Gland began burning at his sanity, the Legion went down an ever darker path.

Legion Armoury

 * Vitrax-Pattern Power Armour: Vitrax-Pattern Power Armour is the name given to any power armour that has been infused with Cameleoline. Due to the properties of cameleoline, this allows the armour to blend into surfaces, becoming almost invisible. The Power Armour also contains an Auspex Scrambler, hiding the suits signature from most auspex devices, however powerful enough auspex can crack through it.This is mainly reserved for the forces of the Caustic Blades, due to the assistance Venun Falkas in its creation. Originally, Vitrax-Pattern Power Armour was made by the Mechanicum by reverse engineering the cameleoline infused armour that Venun Falkas had used on Hemlan. This revealed a way to infuse hard materials with Cameleoline. However, this is relatively costly and is mainly used for officers of the 15th Legion.


 * Corrus Virus Bomb: The Corrus Virus Bomb is very similar to its cousin, the Life Eater Virus Bomb, however on a much smaller scale, being handheld rather than deployed from orbit. The Corrus Virus seems to extremely accelerate rates of corrosion in all materials. This results in a devastating effect on both buildings and living creatures, resulting in a violent and bloody death. Once activated, the gas produced is also highly flammable, making it easy to dispose of once successfully deployed. The prototype for the Corrus Virus Bomb was originally created by Venun Falkas on Hemlan. However, upon his return to the Imperium, he brought the bomb to the Mechanicum who simply gave him a safe casing for it, much improved from the scrapped together original. Now, the Corrus Bomb is almost exclusively used by the Black Coil within the 15th Legion. It is mainly used when targeting enemy strongholds, in which a single bomb would kill all inside and completely devastate the structural integrity.


 * Falkas-Pattern Needler: The Falkas-Pattern Needler is a large, modified version of the Needler, a weapon generally favoured by assassins and similar individuals. The Falkas-Pattern needler takes the acidic substance secreted from a 15th Legion Astartes before piping it to the weapon and crystallising it. The weapon then works much like a normal Needler, but with a significantly more devastating las-blast so it can cut through armour to deliver the acidic substance. Upon the needle containing the crystilised acid entering a body, the acid will be pumped into the bloodstream, leading to a quick and violent death. However the needler may also be filled with various other chemicals if needed. Falkas-Pattern Needlers were originally made by the Mechanicum by reverse engineering the weapon that Venun Falkas had used extensively during his time on Hemlan. In order to make it easier to use, it was given a piping system that leads to the helmet of a 15th Legionnaire in order to easily extract acid from their mouths, so there is no need for refilling. Due to the insistence of Venun Falkas, and due to his help in its original construction, this weapon is specifically given to only the 15th Legion.


 * Falkas-Pattern Chem-Flamer: The Falkas Pattern Chem-Flamer is very similar to a regular Flamer, however, instead of using burning prothium, the Falkas Chem-Flamer uses various corrosive acids and chemicals. The most utilised of these chemicals would be the Bile collected from the mouths of 15th Legionnaires but it can also be loaded with various other chemicals. The Falkas Chem-Flamer was originally designed in order to make eradicating large swathes of low armoured enemies incredibly easy. Due to the nature of the weapon, it can also be damaging to structures and vehicles, making it a very reliable weapon. It has since seen exceeding use in collaboration with the Corrus Virus Bomb. Once the Virus Bomb is detonated, Astartes armed with Falkas Chem-Flamers are sent in to kill hordes of fleeing enemies.