Prefectia Campaign - Opening Moves: Intending to claim another swathe of Imperial space, Aun'Va's expeditionary force had forged a path towards the Gilded Worlds and invaded Prefectia in strength. In doing so, the Tau vanguard had crossed swords with the Adeptus Astartes. Commander Shadowsun quickly took charge, using the Imperials' belligerence against them in a series of classic Kauyon traps.Though the initial clash upon Prefectia had grown intense, the battle for control of the surrounding worlds had barely begun. Bypassing Voltoris as they forged on through the Imperium, the Tau fleets took battle to Doth, Delinquence and Carradon, making inroads into Imperial territory so quickly that the Imperial Navy and the Astra Militarum found them nigh-impossible to stop.As for Prefectia itself, reinforcements were already inbound. No fewer than eight Space Marine Chapters engaged in simultaneous planetstrikes that struck every major landmass within the same terrifying solar hour. The Raven Guard were foremost amongst them. In a remote briefing with Chapter Master Severax, Kayvaan Shrike was ordered to follow up the initial strikes of Shadow Force Solaq, hunting down Tau Commanders amongst Prefectia's electromine complexes. Using the fissure known as Ventur Scar to anchor their operation, Shrike's plan was to assess the Tau, wait for them to commit in force, then dive in to capitalise on the enemy's position. However, the Raven Guard, watching carefully, found not a single vulnerability to exploit -- their stealthcraft was matched step for step by that of Supreme Commander O'Shaserra.The White Scars showed little such restraint. Despatched immediately after Warp translation from Voltoris, the Chapter sent in as many warriors as it could. Kor'sarro Khan organised sweeping assaults across the planet, but took only his most trusted hunters on the quest to slay Commander Shadowsun. With him rode a Stormlance Battle Demi-company of the 3rd Company, elements of the 1st Company and a Speartip Strike. Each of the White Scars was anxious to strike a decisive blow before their Raven Guard allies emerged from their hideouts. At the mention of Shadowsun's name, the Khan's blood ran hot, and his mood became stormy and dark. The grudging respect he felt for her tenacity and skill had not dimmed his desire to claim her head. Yet he would rather it be his glorious blade Moonfang that took her life, not some soot-blackened knife or a bolt in the back. She was a formidable foe, and deserved the clean death he had sworn to exact. The 3rd Company had seen their brothers in the Raven Guard fight with astonishing skill and speed, but that did not mean the White Scars admired their way of war. To hide in the shadows, to watch and wait like assassins in the dark; these notions did not sit well with the Khan.Having engaged her twice before, Kor'sarro Khan knew his foe Shadowsun well enough. He resolved not to strike straight at the city-sized command nexus to the southeast of the electromine complexes. The chances of her being in so obvious a locale were slim to none, and in his opinion, the location was almost certainly the bait for a trap. Instead, the Khan sought to strike the smaller forces she had deployed around the Southern Scars, hoping to drive his nemesis from hiding -- or bring such destruction to her people that she had no choice but to meet him in battle.Within solar hours of making planetfall in the no man's land east of Atlassi Hive, the White Scars had identified three Tau outposts in their proximity, in addition to the command nexus. These outposts, each consisting of several walled hexagonal strongholds reminiscent of the castles of Voltoris, were standing vigil over the speedways that linked the hive cities of the Southern Scars. It amused the Khan to see the Tau adopting the use of defensive structures similar to those that had served Humanity since the days of its infancy; each stronghold had battlements and disc-like towers from which the Tau could rain fire upon any who sought to bypass them. A formidable tactic, to be sure, but one that the speed and ferocity of the White Scars had been honed for millennia to break wide open.The Khan took the measure of his prey like a circling eagle. He despatched his ground forces from Thunderhawk landing sites, giving the Tau outposts a wide berth and attacking them from several directions at once. Yet the hexagonal fortifications too were traps, artifices of deceptive lethality laid as lures for the unwary.After the costly lessons of Voltoris, Shadowsun had dwelt long upon the Imperials' propensity to fortify areas of ground they considered significant. By mirroring this tactic, she led her enemies to adopt the mindset of the siege, and hence fall into a set of interlocking Kauyon traps.The White Scars split their attack en route to the battleground. They assaulted the individual strongholds simultaneously, intending to deny them any chance of mutual support. The Khan's instructions had been to jink through enemy fire with a zig-zagging "forked lightning" attack before gaining the walls and engaging each battlement's defenders at close quarters. But as the thrusting speartips of the White Scars' assaults drew closer, they found the structures themselves rising on cushions of anti­gravitic energy and hovering away from them. The mobile defences slowly gathered pace as the storm of fire from the battlements thickened; they were not large structures at all, but linked collections of Tidewall ramparts that broke apart and moved even as the White Scars charged.The Tau's network of perfect geometric shapes unfolded. Battlements and towers furthest from the attackers divided and moved outward so their extended arms flanked the onrushing White Scars. Perturbed by this development, the Khan ordered his forces to split off, flanking the outstretched arms of the enemy fortifications in their turn. Tau Battlesuits that had been hidden behind each arm were quick to stymie their advance, and the main thrust of each attack found itself enveloped. In moments, the White Scars were trapped in a sleeting storm of plasma that reduced their rugged transports to smoking wrecks.