Jordan, it took me a while to get to it, but here's the flavor text you were looking for.
With the vast power the Reich wields, it is no surprise that a large number of men and women are signing up under the banner of the demonic. Many of these recruits are sacrificed into the great machine of war keeping the forces of the Union, Matriarchy, and others at bay, while the Kaiser and his generals acquire the various items and power they need to strike a decisive blow.
Few of these recruits possess the stomach and internal fortitude to gain entry into the 13th Occult Division. Comprised entirely of those found to be amenable to the U-worlds, this elite body of troopers forms the bulk of the 13th's forces. Able to lay down blistering hails of gunfire, stand coolly in the face of the otherworldly, and remain completely loyal to the Kaiser, these soldiers are the pinnacle of grunt soldiers.
As the pacts between the Reich and the U-worlds grow stronger, many Schocktruppen have begun to show signs of the budding alliance. The leaders of the 13th have taken this as a sign of great things to come. What the SChocktruppen think is considered irrelevant.
Consummate killers, the former men and women of the Stosstruppen are now utterly without pity, fatigue, remorse, or anything resembling human emotion - aside from rage. More demon than human, these living engines of destruction seek only to shed the blood of the enemies of the Reich.
Although the Stosstruppen still bow to the authority of their superior officers and attempt to follow the strictures of the Obscura Korps, many officers feel that these twisted hybrids are best left in chains or behind enemy lines.
Von Heïzinger and his bodyguard Karl Zermann favor using these creatures as their ties to the otherworldly have given them a better understanding of bargaining with the demonic.