You get rules for playing as a Battle Sister. They are even well balanced. What more do you want?

Genuinely adds a great amount to the background and also provides some interesting new character options. Only real gripe is I found some of the plot ideas they gave pretty vague and washy.

This latest system update to Dark Heresy 2.0 perpetuates the science fantasy (as opposed to science fiction) of the Warhammer Universe, but unlike earlier attempts to provide players and gm's with useful tools for creating engaging sessions I believe that Enemies Within is a solid step in the Right direction. While not nearly as robust in its gm toolkit as systems like Stars Without Number, this book none-the-less provides gm's with setting-appropriate adventures in the vein of the Abnett's Eisenhorn stories and Sandy Mitchell's "Innocence Proves Nothing." To me, the most engaging stories of 40k's grimdark are the those where ill- or mis-informed but no less goodly and skilled servants of the Imperium carry their torch into the deep and the dark places, look into the madness that therein dwells, and fight feverishly to burn out that rot with cleansing flame, and this supplement, more than any other fantasy flight has since put out, is their best effort to allow players fulfill that fantasy.

So, Acolyte, where do you look for heretics? Do you find them clearly on view, participating in foul rituals as part of organised cults that anyone may join? Or do you sometimes look closer to home...? Many cults start off benign and drift - often without intent, unwittingly even - astray. There's no knowing where you will find heresy and mutants, especially within the ancient worlds of the Askellon Sector.

This book delves deep into this often hidden menace with particular reference to the Askellon Sector in three chapters. The first looks at the history of the Ordo Hereticus, the second provides new options and rules information and the final chapter explores the worlds of the Askellon Sector and the cults lurking thereon.

Chapter 1: Hereticus details the origins, history and operations of the Inquisitors of the Ordo Hereticus, also known as Witch-Hunters, whose purpose is to protect mankind from the threat of betrayal from within. They seek out corruption and burn it, often fairly indiscriminately. They are zealous to a fault and do not like being thwarted. Even those who welcome them frequently regret it. Their origins are shrouded in mystery and they go to great pains to keep it that way, prefering to work in secrecy and without accounting for their actions to anyone. They would prefer to burn hundreds of innocents to get a heretic or two, than let even one get away. They also treat their Acolytes as disposable assets, so take care before you take service with such an Inquisitor.

There is plenty more here too: organisations of witch hunters and some of the cults that they pursue. There are details of the many and varied philosophies that they hold, which must lead to some interesting debates when several are gathered together.

Next, Chapter 2: Fury and Fire looks at new options and additions to the rules, beginning with a selection of new home worlds that you can select. These are of general interest even if you want to steer clear of the Ordo Hereticus. Perhaps an agri-world, a feudal one or a frontier world appeals. Next are the Orders Militant of the Adepta Sororitas — a background of warrior women in service to the Ecclesiarchy. More risky, you might choose a background as a mutant, that is, one born a mutant rather than having acquired mutations later on in life. New roles such as the fanatic and the penitent are also discussed. There is also an array of new (and vicious) weapons as well as new armours in which to encase yourself. A select of profane artefacts is followed by specialised talents described as the Art of Hatred, for the Ordo Hereticus is fuelled by hatred of their heretical prey rather than any compassion for those whom they would protect from them. Finally there is an account of the process known as an Inquest, the specialist form of investigation used by the Ordo Hereticus to uncover heretics, reflecting their somewhat casual relationship to truth and justice and quantifying it in game mechanical terms.

The final chapter is Roots of Heresy, and this is a detailed look at the worlds of Askellon with special reference to the heresies to be found thereon. Game Masters will find it very useful, as it spawns plenty of plot ideas, moreover there's also a section on how to create heresies of your own as well as how best to present the tell-tale signs to knowing Acolyte eyes.

There's plenty of information to draw on here, painting Askellon as a far darker place that the Calixis Sector featured in Dark Heresy 1e. Perhaps that's due to the sector's age, for with age it seems comes decay and corruption. Of course, my mischievous mind promptly wonders what happens when someone within the Ordo Hereticus itself slips over the edge, turns bad and embraces heretical ideas and practices? Or are their excesses a sign that this has already happened? Whether your Acolytes choose to serve the Ordo Hereticus or encounter them as they go about their business, this book will help you bring it all to life. Pass the torch...