The 189th Tebessan Expeditionary Force is a combined regiment drawn from the sparsely populated but resource-rich Imperial mining world of Tebessa. This small, backwater planet is located in the outer reaches of Segmentum Tempestus. It is rich in heavy metals, giving it close to standard gravity. It is also tidally locked to its nearby star Idrissia Secundus, leaving the near side in perpetual daylight, and the other in constant night separated by a temperate but storm-ravaged “twilight ring”.
The day side is mostly a harsh, baked desert tending towards scrub and savannah in the temperate twilight ring that bisects the planet between the day and night regions. Due to the abundance of solar energy, most of the planet’s industry is centred on the day side, with population centres closer to the twilight ring. The day-siders are industrious and resourceful, using technology to thrive in the otherwise inhospitable landscape. The mineral wealth they export to the wider Imperium allows them to procure modern arms and armour.
The dark side of Tebessa is a barren wasteland populated by nocturnal predators and hardy plant life that has adapted to photosynthesise in the weak light given off by radioactive isotopes present in rocky outcrops. It is also home to the Alllayl (meaning “of the night”), a race of nomadic hunter/gatherers. These resilient and insular people have diverged significantly from the day side population in both culture and genetic makeup in the 8 millennia since Tebessa was settled. They possess lighter skin than their day side cousins, and excellent night vision.
Tebessa’s history is dotted with cross-cultural tensions and short, bloody incursions by Alllayl raiders in times of food scarcity. Relations between the two populations have also been strained by mineral exploration teams from the industrialised day side making inroads into the tribal lands of the night-siders in search of the rich metal seams that dot the planet’s surface.
The appearance of Imperial missionaries in M.38 did much to unite Tebessa under the Imperial creed. These pious and hardy individuals gained the respect of the night-siders by travelling alone and on foot, deep into the frozen night lands to spread the Emperor’s light.
The day side population were also brought into the fold, gladly offering men and resources to humanity’s war-effort in exchange for spiritual enlightenment and trade opportunities. A small percentage of the day side population have taken their devotion to the Emperor to the extreme. This fanatical sect, calling themselves Masar Alambratur or The Emperor’s Path, long to die as martyrs in the Emperor’s name. These religious zealots are often shunned by the wider Tebessan society, but Imperial commanders value them as strategic assets, often deploying them in small kill-teams behind enemy lines.
More recently, an increase in Tebessa’s Imperial tithe grade has necessitated recruitment from among the Alllayl population. The day-siders have offered modern weapons, equipment and supplies in exchange for volunteers to join the ranks of several newly-formed Imperial Guard regiments. These volunteers bring with them a unique skillset which makes them excellent trackers, scouts and snipers, but their adaptable nature means they are also found in other roles in the Tebessan regiments.

The vanguard of the 189th Tebessan Expeditionary Force is the XIV Tebessan Armoured Company, Led from the front by the charismatic Colonel Faizal Danek, riding in his heavily modified Leman Russ Punisher “Emissary”. Danek wears traditional Alllayl headscarf and ceremonial blade as a mark of respect to the night-siders who fill out his ranks. The company is made up of heavy armour and mechanised grenadiers.

The remainder of the force is made up of the 1st Alllayl Reconnaissance Division, who act as scouts and light infantry, and the 6th Commando Battalion; elite shock troops outfitted with a mix of Militarum Tempestus and locally produced equipment.
Elements of the XXVII Tebessan Artillery Company and the Imperial Navy 46th Strategic Air Command support the main force in lager engagements, as well as guerrillas from the Emperor’s Path sect.
At time of writing, the 189th Tebessan Expeditionary Force has been blooded against a variety of xenos foes. Scoring two notable victories against Eldar Raiders in the Ixaniad Sector of Segmentum Obscurus, they have also encountered Tyranids and Greenskins.