- "Infantry wins firefights. Tanks win battles. Artillery wins wars."
- — Old saying amongst Imperial Guard artillery officers
An Imperial Guard Operator is a rare specialist of the Imperial Guard who feels unusually comfortable around the Machine Spirits of the ancient devices utilised by the military forces of the Imperium of Man. Advanced technology in the late 41st Millennium is now more of an arcane science, dabbled in by a rare few, and truly understood by none. However, these great works of ancient science are what keeps the "Hammer of the Emperor" rolling forwards, crushing the foes of the Imperium. Operators are highly valued by their commanding officers, for although they do not possess the knowledge of the Enginseer and other members of the Adeptus Mechanicus, they are competent enough to rouse the Machine Spirits into action, and use them to great effect in battle. Whether these men are piloting a mighty Leman Russ Tank into the heat of battle, operating a Vox to relay a commander's orders, or performing litanies on jammed Lasguns in the trenches, these men are indispensable to the Imperial war machine.
Those Guardsmen who work with the war machines of the Imperial Guard fall under the Operator specialty, and as with other Guardsmen specialties, Operator is not an official title, as these men and women are called many different names across the Imperium -- for example, the Lacustan 103rd affectionately refer to men in their armoured squads as "tread-jocks." Operators are an invaluable asset, and can quickly rise in the ranks if they survive the brutality of combat. Some eventually become a Master of Ordnance, calling in titanic orbital bombardments upon their enemy. Others are given charge of the various war-machines fielded, commanding Chimera armoured transports, Leman Russ battle tanks, and sometimes even a mighty Baneblade super-heavy tank. Whatever his function, it is sure that the Operator will bring the Emperor's wrath down upon his foes.
- Standard Imperial Guard Regimental Kit
- Auspex/Scanner - The standard Imperial detection device, these are used to detect energy emissions, motion, biological life-signs, and other information.
- Mind Impulse Unit (MIU) - These devices, also known as sense-links, allow the owner to interface directly with a machine or technological device. MIUs see widespread use among the Adeptus Mechanicus, who regard them as objects of divine communion with the Machine God. A basic MIU implant involves a single spinal or cortex connector, while advanced variants include wrist connector probes—and possibly mechadendrite connectors—in addition to the spinal plug.
- Combi-Tool - Commonly found in the hands of members of the Adeptus Mechanicus, Combi-Tools are versatile, if somewhat bizarre, mechanical devices.
- Data-Slate - Data-Slates are common in the Imperium and are the primary means of storing and reading printed text and other digital media such as video or audio recordings. They are cheap and easy to make, and many contain a single media recording, such as text, and can only play that single file. Others can record new information or transmit and receive data from other devices.
- Lascutter - Ideal for slicing open doors and bulkheads, Lascutters were originally designed for mining where their short range but intense laser cutting beam could chop apart even the toughest rock. Most models can cut or weld around 10 centimeters of metal depending on the thickness involved. They are large and cumbersome to use, however, precluding their effectiveness in combat situations.
- Only War: Core Rulebook (RPG), pp. 80-81, 200-202, 208