The 99th Deltic Gorgonnes is a Tempestus Scions regiment of the Militarum Tempestus that has earned great renown as slayers of the vicious monstrosities known as Tyranids. Most recently, the Gorgonnes assembled a surgical strike brigade to provide safe exit for Planetary Governor Vallera Dresis during the Xariss Campaign ahead of the encroaching invasion of Hive Fleet Leviathan. The regiments of the Catachan Jungle Fighters were demoralised after a previous campaign against the Tyranids, jeopardising the operation, and so the Deltic Gorgonnes were tasked with this vital duty.
- Bitter Salvation (997.M41) - Less than five standard years after the defeat of Hive Fleet Kraken in the Second Tyrannic War, the Imperium took note of the tell-tale signs of yet another Tyranid invasion in 997.M41. Codenamed "Leviathan", this time the Tyranids were approaching from below the galactic plane, attacking from two points spaced wide apart in the shape of a closing pair of jaws. At a great cost in human life, the Imperial forces managed to secure a victory on Tarsis Ultra, destroying the Tyranids nearest to Terra, and reestablishing astropathic contact with the worlds between the Leviathan's jaws. Yet Leviathan continued to carve its bloody path through the Imperium. To slow down the Hive Fleet's advance and buy time for the Imperial Navy's Battlefleets Solar and Tempestus to muster, a cordon was established. Every world within was to be evacuated and undergo immediate Exterminatus wherever possible. Xariss was one such world. The Planetary Governor Vallera Dresis was deemed essential personnel and worth saving. Commissar Decius Krassus, brother of Tempestor Prime Magnus Krassus, was given what should have been a simple mission: to smuggle out the Planetary Governor of Xaris ahead of the Tyranid invasion. Commissar Krassus' orders were to take the nearby Catachan MDCCCXLV Regiment and escort her off-planet. The Catachans had recently suffered heavy casualties after fighting Tyranids on a nearby Shrine World, where they lost eighty-three percent of their regiment. Four hundred men remained, mostly new recruits. The first waves of the fatigued and dispirited Catachan MDCCCXLV sent forward into battle were insufficient. Even those veterans who had faced the Hive Fleet before were unable to hold their ground. Krassus promptly executed those troopers who foolishly displayed insubordination, and assumed command, spearheading advances personally. Finally, Krassus received a Vox-message that the 99th Deltic Gorgonnes, led by Tempestor Prime Cadmur, were making planetfall amidst Leviathan's deluge. Once the Scions made planetfall and hooked up with the Commissar's forces, they confirmed Krassus' orders, and proceeded to jointly cut through the swarm to reach the governor's compound. When the Imperial troops reached the compound, they were confronted by a new threat -- many Imperial servants within sported strange tattoos and droned allegiance to the Dark Gods. The Imperial forces were forced to slaughter scores of these Traitors. Tempestor Prime Cadmur discovered a terrible truth about the governor, that she too, had also turned to Chaos. Cadmur and Krassus had clear orders to retrieve Vallera Dresis, and that was precisely what they were going to do -- even if she had given herself to the Ruinous Powers. Subduing the rabid Vallera Dresis with tranq-injects, the Scions bound the governor and took turns to carry her through the corridors. As they advanced, the Imperial forces encountered multiple Tyranid bioforms, each more terrible than the last. As they fought their way clear of the compound, the 99th laid explosives in their wake, buckling the gates of the palace and sending rubble flying in order to block the creatures' progress. The surviving Imperial forces were extracted by several Valkyries as they raced across the darkening skies towards their prearranged evacuation point. Eventually, the Scions secured a safe landing zone for their transports. Krassus and the Catachans were the first to board. As the Valkyries lifted off, the governor awoke to find herself looking directly into the barrel of the Commissar's Plasma Pistol.
The Tempestus Scions of the 99th Deltic Gorgonnes primarily wear dark gray-coloured fatigues with green-camouflaged Carapace Armour with silver-coloured trim. Their poleyn (knee guards), Slate Monitron and Omnishield Helms are also painted in this green camouflaged-colour scheme. The faceplate of their omnishield helm are silver in colour.
The regimental symbol of the 99th Deltic Gorgonnes is a green coloured three-sided polygon, believed to be an ancient symbol of Terran origin, but whose exact meaning is unclear. The orientation of the point-up triangle might represent a strong foundation or stability, as it is rooted to the ground through a solid base. These characteristics of stalwartness and stoicism in the face of adversity run strong within the 99th Deltic Gorgonnes, making the triangle an apt symbol indeed.
- Codex: Militarum Tempestus (6th Edition), pp. 39-40