*''[[Xanthism]]'' - The most obviously Radical grouping within the Inquisition, it advocates the use of warp-based weaponry, such as daemon possessed swords, daemonhosts, and generally turning the power of [[Chaos]] against itself. Named after Inquisitor-Master '''Zaranchek Xanthus''', executed as a heretic in the 32nd millennium.

*''[[Recongregationism]]'' - The Imperium, after millennia, has become decadent and corrupt according to this philosophy. To remedy this, Recongregators consider that the Imperium should be rebuilt, lest it stagnate further and collapse under the pressure of countless threats from both without and within.

*''[[Istvaanism]]'' - To this ideology, conflict is desirable to further progress through strife. It holds that mankind has made its greatest achievements after periods of conflict, such as the [[Horus Heresy]], or [[Age of Apostasy]]. It is the place of the Istvaanians to strengthen mankind through adversity, and so follow a 'survival of the fittest' doctrine. The philosophy is named after the [[Isstvan III]] [[Virus bombs|virus-bombings]] that initiated the Horus Heresy.