Vlenn Brodaack was an Imperial Guardsman. As with most Guardsmen, he had been conscripted into the righteous service of the Holy God-Emperor of Mankind at the age of seventeen. His homeworld had been an agri-world, devoted to the production of food. Not that it mattered to him anymore. A Guardsman never returns home, and the rich endless fields of grain and illustrious woodlands of his homeworld were forever separated from him by the eternal, dark voids of space.
After basic training Vlenn's regiment soon got its first assignment. The 2,000 men, alongside tanks, artillery pieces, and numerous support vehicles, were sent to a world besieged by mankind's oldest enemy: the Orks. The planetary defense forces were able to halt the foul xenos invaders but lacked the manpower necessary to push the numerous Orks off the planet. Sector Command had sent Vlenn's regiment, alongside others, to reinforce and support them.
The war had lasted 12 years. Slowly but surely the methodical tactics of the Guardsmen won out over the Ork's savagery. Imperial casualties were actually relatively low. Any Guardsman who was collected and careful had a decent chance at survival. The Ork attacks were unorganized and haphazard, usually resulting in them getting mowed down by Imperial auto-cannons, las-cannons, frag missiles, and lasfire long before they managed to reach the hand-to-hand combat they craved.
Likewise, the Ork defenses were ramshackle and unimpressive. Imperial artillery could reduce Ork forts to rubble within a matter of weeks, killing everything inside. Oftentimes, Ork vehicles or war machines would malfunction or explode due to the poor quality of their Mekboyz construction efforts as much as to the firepower of Imperial weapons. At the end of the twelfth year every Ork on the planet was dead, and Vlenn's regiment was up for re-assignment.
Vlenn was a quiet man. Determined, quick, steady. Twelve years of fighting had washed him clean of most other emotions. Anger, sorrow, happiness… there was no room for them. They were a dangerous distraction; men had died from them because they weren't paying attention to the battlefield around them. Find the enemy, take cover, aim, fire, repeat. That was what Vlenn focused on for twelve solid years. That is what he remembered. But even for all that, the hardened veteran felt a small sliver of fear in his heart when he heard where they were headed next….
A former Imperial world now under Chaos control. A large battle was currently being joined by Imperial and Chaos forces throughout the region, and this world was vital to the supply efforts of Chaos. Its loss would be devastating to them. However, it was not undefended. Massive cannons dotted its surface, designed to repulse enemy starships; and the Imperial fleet was spread too thin to try and overwhelm them by sheer force. This is where Vlenn's regiment came in.
They would land on the planet, the troop landers being small enough to evade fire from the ship-killer canons, and advance toward their city-sized target to destroy the generators that powered the cannon. Other battle groups would do the same to the other cannons at the same time, limiting the ability of the Chaos armies to reinforce one another. After the massive cannons were powerless a few Imperial ships would bombard the planet to destroy the Chaos-controlled space stations and manufacturing centers, cutting off the supplies to their larger war-effort. Simple, right?