Space Marines experienced in operating independently and behind enemy lines form dedicated Reconnaissance squads within the Legiones Astartes. Equipped with a variety of specialised wargear including long-range sniper weapons, stealth gear, and augmented sensor-auspex devices, Legion Recon Squads function as scouts, gathering intelligence and mapping enemy movements and strengths.

Reconnaissance squads also serve their Legion as pickets, saboteurs, raiders and snipers where needed, striking at high-value targets of opportunity. In open battle, they are expert in sudden flanking manoeuvres and infiltration attacks in support of the main strength of the Legion.