Editing Parthorum Xenocide (section)

==Southern Theater Battles ==
[[File:Parthorumstream+south.jpg|thumb|left|250px|Diagram of the Parthorum Stream relative to Terra.  The limit of the Southern Theater is shown by the dotted blue line.]]

First Legion's initial objectives fell in the southern reaches of the Parthorum Stream, a region roughly 50 light years in each dimension.  Rogue Traders had already roughed out the shape of subsectors based on Asturus, Hucrov, Iuybos, Scomia, and Ublade, but during the Parthorum Xenocide First Legion's commanders referred to this vast area of space as the Southern Theater.  The Osroene were aware of the limitations of their technology and relied on strong planetary defences to hold up invaders until one of their great fleets could arrive and decide the action.  Adela Exard had obtained records of such relief actions against Gallvi raiders in popular histories and Hektor Cincinnatus drew up his plans accordingly.  Rather than disperse his forces to planetary assaults and risk being defeated in detail, the Primarch's first target was the "Southern Fleet" that patrolled the region.

Hektor used Rogue Trader vessels under First Legion officers to surreptitiously hunt for the Southern Fleet.  Astropathy allowed a report from the Destoona system to be follow up on sharply and the Xenos were soundly defeated in the [[First Battle of Kopt Dara]].  However, Imperial losses compelled Hektor to return his fleet to Mars.  In order to expedite the process, Fabricator-General [[Kalkas Tygian]] personally commanded two Mechanicum warships, the ''Revelation of Victory'' and the ''Rites of War'' to take the place of the crippled First Legion cruisers ''Mount Ararat'' and ''Blessing of Thunder'' for the remainder of the campaign.  This generosity and the sterling efforts of the Mechanicum had the 3rd Expeditionary Fleet ready to resume its offensive at 201/811.M30.  Hektor split his command into three.   His own ''Chrysaspides'' formed the reserve, while the First and Second Phalanxes, reinforced with substantial fleet assets, were detached to independent compliance operations.

Erasmus Sergius's First Phalanx launched a three-pronged campaign into the Hucrov subsector.  By 293/811.M30 the lone planetary fortress at Hucrov-6 had fallen to Space Marines deployed by Thunderhawk and the planetary government capitulated rather than face annihilation at the guns of the Imperial fleet.  Nearby Thucerus was better-defended and its orbital installations had to be reduced by First Legion's warships before occupation began, but again the defenders swiftly surrendered once their space defences were neutralised at 295/811.M30.  Only at Xabradus did Sergius's men face sustained resistance.  Here small teams of Space Marines were once again successful in disabling the planetary fortresses, but the ground defenders remained resolute.  With reports of a substantial human population on-world, Strategos Bacchides Floridius felt unable to conduct a strategic bombardment and instead committed further ground forces to the surface.  Floridius's naval support, in particular the sophisticated ''Rites of War'' did carry out tactical and operational bombardments, acting as orbital artillery for the Space Marines below.  Xabradus was declared pacified at 303/811.M30 and handed over to a powerful garrison based around regiments of [[the Carlisian Shock Troops]].  Supply records indicate that the auxilia were still mopping up resistance for months to come, but the Adeptus Astartes were free to continue their conquests.

Second Phalanx, commanded by Lysimachos Fabius, were free to concentrate their efforts on the well-defended Scomia system.  Like their battle brothers at Xabradus, the warriors of the Second were glad to have a Mechanicum warship with them.  The advanced armament on the ''Revelation of Victory'' out-ranged the defenders' void weapons.  Although Fabius was not prepared to engage in a lengthy stand-off engagement, ''Revelation of Victory'' badly damaged one of Scomia-2's orbital fortresses shortly after the void battle began at 292/811.M30.  This good fortune allowed Space Marines to make surface and take out the planetary guns before the void battle drew to a close.  The Imperial fleet finally disabled all three orbital installations and commenced landings in force at 294/811.M30.  Osroene troops put up a spirited resistance but the thousands of Space Marines under Fabius's command harried them relentlessly, waging around-the-clock warfare that the Xenos were physically incapable of withstanding.  Second Phalanx signaled at 317/811.M30 that organised resistance on Scomia-2 had ceased.

Although Hektor was pleased by the progress of his gene-sons, he was anxious to capitalise on what time remained before the Osroene could respond in force.  Determining on a bold course, he signaled Mars to request additional voidships and took his own ''Chrysaspides'' back to Destoona.  The system's main inhabited world, Jeglora, was secured at 370/811.M30.  This attack briefly seemed like recklessness when a large Osroene fleet arrived in system at 418/811.M30, but Hektor's void tactics allowed his command squadron to stay clear of the aliens until Mechanicum reinforcements led by [[Zorr Yenser]] arrived at 445/811.M30 and forced the decisive [[Second Battle of Kopt Dara]].