Battle of Calth - Final Assault: Simultaneously on the beleaguered surface of Calth, the 4th Company struck along the Ketar Transit, a main access route that linked the container storage area to the northern facilities of the port at Lanshear. Their target was the data-engine of the Cargo Handling Guild located in the bunker system below the majestic edifice of the guildhall.Ventanus led the foot advance across the broken streets himself, behind a column of Land Raiders. Word Bearers Astartes rose up to block the Loyalists' advance. Instead of overwhelming the Loyalist forces with well-directed firepower which might have broken or turned Ventanus’s charge, the Word Bearers simply waited for the inevitable clash of close combat. They relished the prospect of testing their Chaos-corrupted blades against the vaunted Ultramarines in hand-to-hand combat.The Traitors wanted to prove themselves against the Astartes who had been held up to them so many times as the models of what it meant to be Space Marines. The charging cobalt-blue warriors of the Ultramarines met the solid crimson line of the Word Bearers with a crash. The fighting proved both brutal and unforgiving with neither side asking for, nor receiving, any kind of quarter.Reaching the guildhall, Ventanus leapt the barricades, leading the assault forward. He tore into the fleeing Chaos Cultists who shrieked in fear at the prospect of facing the fierce Astartes officer. As the Ultramarines moved forward into the building they continued to be pounded by the XVIIth Legion's artillery and heavy weapons. Reaching the Cogitator that was their goal, Magos Tawren attempted to connect into it and upload the kill code that would shut down the planetary defence grid.As the magos concentrated on gaining access to Calth's planetary defence system, the Loyalists' fate took a turn for the worst. The forces of the XVIIth Legion's Commander Hol Beloth descended upon the guildhall with a vengeance. He had come to punish the hated Ultramarines with a force of Traitor Titans, the Word Bearers' Terminator-armoured Cataphractii and the dreaded daemon-possessed Astartes of the Gal Vorbak.The situation became grim for the Loyalists. Traitor Titans continued to fire upon the guildhall until its very foundations began to shake from the constant pounding. Ventanus checked with Tawren for a status update, but progress was slow as the magos attempted to establish her cybernetic neural connection with the server.The situation outside was rapidly deteriorating as armoured columns in service to the Word Bearers moved into position and began firing at the Loyalists with a hail of shells and laser fire. Two Traitor Reaver-class Titans approached at full stride, intent on annihilating the servants of the Emperor. With the majority of his allied commanders already dead, Ventanus knew that his company line was all but broken.The Ultramarines of the 4th Company had done all that they could do, for they could not stand against the overwhelming strength of Hol Beloth’s offensive. The weapons fire intensified as the Titans continued to pound the guildhall. Tawren finally managed to upload the kill code into Calth's network so that she could prepare to purge the planetary data system and wrest control back of the defence grid. But until that control had been wrested away from the enemy, there was nothing that she could do to aid the shrinking force of Loyalists.As the Titans moved closer to the guildhall, the last Shadowsword accompanying the 4th Company fired and damaged one of the striding giants, but the pair of Titans returned fire in unison, destroying the super-heavy tank in a vast conflagration of Titan-grade weapons fire. Ventanus knew then that their attempt had all been for naught. The Traitors of the XVIIth Legion had seemingly won the Battle of Calth.