Sentinel Guard Sodalities are deployed to protect emissaries on hazardous ground and hold defensive positions against the most grievous onslaught. They are outfitted with energy field-reinforced ‘praesidium’ shields – a precursor to the Legiones Astartes’ storm shields – capable of resisting the heaviest weapons fire. In spite of this protective role, the physical prowess of each Custodian, and the peerless wargear with which they are outfitted, also affords the Sentinel Guard the mobility to perform far more aggressive functions in open battle, where their resilience makes them formidable.