Caius was busy once the Cadian 88th had reached the Cathedral, rushing from position to position, helping the various groups fortify their entrenchments. One group he helped dig a small trench to fill with jagged wood and metal spikes taken from the rubble. Another he fixed up a heavy stubber for, deploying it against a collapsed pillar supported with rubble. The defenses grew steadily in preparation for the oncoming assault. His thoughts were as much a blur as his movements, jumping from thinking about how best to set up a rubble blockade at the east wall, to a series of quick prayers to the God-Emperor. He frequently found himself rubbing a hand across the golden aquila pendant he had scavenged from earlier, whether for luck or last wishes, he knew not. 

When the time came for the inevitable Greenskin assault, he found himself in the main entrance to the massive building, tasked primarily with keeping one of the last heavy bolters around running properly. As the horde of xenos washed over the horizon, he and many others began to unleash wave after wave of lasgun, stubber, and bolter fire, doing their best to drown the alien menace in projectile death. Yet the greenskins persisted, growing angrier and stronger, speeding closer to the encampment. But still Caius fought on, his lascarbine screaming at him in the language of machines, heat venting from every possible exit, the charge pack steadily draining of its energy as it fueled the weapon. Caius' well disciplined shots of Caidan marksmanship brought down many a greenskin, though they still charged closer. Eventually, some of the smaller, faster greenskins would reach the line, scrambling up the rubble defenses to engage the guardsmen in hand-to-hand. Caius drew his knife and charged right back at them, screaming a blood-curdling cry of "For the Emperor!" as he tore his way through the smaller aliens, just in time to regain his position for firing at the larger beasts. Realizing his combat knife and lascarbine would be ineffective for engaging the larger Orks, he 'requisitioned' a bayoneted M36 from a fallen ally, whispering the Emperor's Peace to his fallen comrade as he did so. When the full-size Orks reached their wall, he was quick to use his lighter speed and smaller size against each foe, ducking around and behind them, jabbing at their exposed flesh with fast thrusts, preferring to maximize strikes over damage. One greenskin presented a particularly big opening, bellowing out a massive, enlongated cry in its guttural tongue. Caius took this chance, unhooking a frag grenade from his web belt. He pulled the pin and lept at the beast, attempting to lodge the grenade within its massive mouth. Unfortunately the Ork caught on, reaching to smack him out of the way. The massive hamfist grazed Caius' side, shattering a few ribs, and knocking him away, the grenade flying off into the melee around them, detonating and killing Xeno and Guardsman alike. But still Caius stood to his feet, spitting and wiping the blood from his mouth, raising his bayoneted weapon, and charging back into the fray, more furious than ever before. As he did so, his thoughts turned to one statement...

[i]I may be just a man, armed with a simple weapon and not much more. But I am strong. I am Human. I am the Imperial Guard, and I will hold the Throne-damned line.[/i]