Battle of Prospero - Main Contingent: The VI Legion, the Space Wolves -- comprising an approximate total of 73,200 Space Marines, including contingents previously on detached duties in proximity to Fenris or Beta-Garmon, and recalled for the Prospero campaign. (Companies are noted here using both the numerical designation used by the Divisio Militaris records and the more archaic titles used during available recitations of the Saga of Prospero -- additional notation of current observable operational factors from Beta-Garmon data included):Great Company Onn (One), "The Breakers of Rings", commanded by Jarl Gunnar Gunnhil (Lord Gunn). 3,000 Space Marines, primarily formed of Varagyr Huscarl units equipped with Terminator Armour and fighting as bodyguard, and also comprising additional Legion command elements.Great Company Twa (Two), "The Thread-cutters", commanded by unknown Jarl. 800 Space Marines, believed to comprise veteran infantry units relived from special duties with attached Dreadnought contingent (approximately 60 individual armours of varied patterns). Jarl unknown.Great Company Tra (Three), "The Eagle's Keepers", commanded by Jarl Ogvai Ogvai Helmschrot. 9,800 Space Marines, mostly close assault infantry and support armour (noted in extemporaneous data as being proportionally high in Initiate-status Legiones Astartes).Great Company For (Four), "The Blood-worm's Masters", commanded by Jarl Hvarl Red-Blade. 8,600 Space Marines, comprising heavy infantry and self-propelled artillery, including a large number of Breacher and Assault units (ref. "Bloodied Claw" tactical formation sub-type).Great Company Fyf (Five), "The Blood-ice Storm", commanded by Jarl Amlodhi Skarssen. 10,000 Space Marines, comprising a mixed infantry force with light support armour, assigned while on Fenris for resupply.Great Company Sepp (Seven), "The Wight-flame's Wielders", commanded by unknown Jarl. 5,200 Space Marines, comprised mostly of warriors of the "Black Cull" and destroyer and immolation units.Great Company For-twa (Eight), "The Slaughter-fire Heralds", commanded by unknown Jarl. 9,500 Space Marines, comprising principally reconnaissance and infiltration units (ref. "Pale Hunter" tactical formation sub-type).Great Company Tra-tra (Nine), "The Serpents of the Battle-moon", commanded by Jarl Sturgard Joriksson. 7,800 Space Marines, comprising infantry support units and notable heavy weapons units, including Rapier weapons platforms.Great Company Elleve (Eleven), "The Sea-flame's Bearers", commanded by Varald Helsdawn. 9,200 Space Marines, comprising veteran infantry, believed to include a large proportion of early-induction Terran recruits.Great Company Tolv (Twelve), "The Shield-gnawers", commanded by Jarl Oki (called Scarred; successor to Jaurmag (called Laughing Jaurmag, who was sent to Terra before Prospero campaign). 8,700 Space Marines, comprising close assault infantry with strong contingents of ground assault vehicles.Great Company Dekk-Tra (Thirteen), "The Corpse-renders", commanded by Jarl Jorin Bloodhowl. 600 Space Marines, comprising pursuit units and light assault infantry.Legio Mortis - Twelve Battle Titans of the "Death's Heads," forming two full maniples and one demi-maniple, including the Warlord-class Aeterna Virtus as its command element.19th Cthonian Headhunters Regiment - Slightly less than 9,000 assault infantry raised on Cthonia, infamous within the Imperialis Auxilia for their savage and belligerent temperament and tendency to mutilate the dead for trophies.3rd Ydranian Seekers Regiment - Light infantry from the Ydran Cluster, notably a sector of Human-occupied space devastated by rogue psykers prior to Imperial Compliance at the hands of the Death Guard. Organised into three cohorts of 4,000 soldiers each and believed equipped with a variety of non-standard psi-warding technologies -- the effectiveness of which was deemed dubious by the Mechanicum.73rd and 75th Echelons of the Hosts of Brass - Heavy infantry. Notably recruited from the sub-tech world of Brass, whose feudal lords long indoctrinated the population against the potential threat of "sorcerers" and other psychic phenomena. Numbering 8,000 per cohort and equipped with a variety of primitive but effective close assault weaponry and chemical slugthrowers.