Author's Notes for Legion of the Dead: A "culture article" for the Marian Hegemony, rather than a formal Unit Digest, the backgrounds of the characters are intended to showcase life in the Hegemony in the late 3140s/early 3150s, and what sort of things could get someone remanded to the Cohors Morituri. Not just psychotics and base criminals, but also people who followed the dictates of their conscience in contravention of Caesar's will, or crossed the wrong Senator.
Checking the Era Report/FM: 3145, Shattered Fortress, and Empire Alone battle records, it appeared that the Cohors Morituri remained on garrison duty throughout most of the recent fighting. This means that, compared to the battered regular Legio formations, the Morituri are, in fact, one of the strongest and freshest combat units in the Hegemony as of 3152.
Given the mish-mash of personalities thrown into such a penal unit, it'd make a great RPG setting for those inclined to deploy alongside a "sordida duodecim." Plus, there's the chance of doing well enough to get a pardon, contingent on taking on special ops for the Ordo Vigilis (Suicide Squad-style).