The Skull Probe is a military device utilised by Loyalist Space Marine Chapters for reconnaissance. It appeared as a skull-shaped drone that hovered a meter above the ground, so it appeared to be a variant of the anti-gravitic Servo-skull commonly used by a wide variety of Imperial Adepta. It was capable of stealth and quick flight that was faster than most units could move on foot, though it could not hover over obstacles. A Skull Probe is valuable to the Space Marines as a scouting unit for its mobility and inexpensiveness, though they were unarmed and quite fragile. They were able to temporarily neutralise an enemy structure, allowing the Space Marines a temporary tactical advantage, though this usage would destroy the skull in the process.