A Marker Drone (Kor’vesa in the Tau Lexicon) is a type of Tau Drone (small, sleek, disc-shaped, semi-sentient machines) employed extensively alongside Tau units in battle. Marker Drones are primarily equipped with a Marker Light, which it can use to designate targets for other squads of Tau warriors. The Marker Light can then feed targeting information to the squad to drastically improve the effectiveness of their firepower. Some Marker Drones have also been known equipped with a Targeting Array to augment its own accuracy when using its Marker Light.
Marker Drones consist of an advanced processor unit, which individually has only a basic intelligence (approximately that of a small animal such as a pterasquirrel), and moves about by way of a small anti-gravitic generator and a smaller and much modified version of a Tau Jetpack. This allows the Marker Drone to hover over the ground and skim over most obstacles. As they hover over landscapes, rotating back and forth, their sensor vane constantly transmits vital information about their surroundings.
In battle, Marker Drones will commonly serve under a Tau officer who commands it through the use of an electronic device known as a Drone Controller. Marker Drones that are attached to a Tau squad can be controlled by a Drone Controller, whether it is in the form of a support system for a Tau Battlesuit, or a hard-wired piece of wargear for Tau infantry. A Drone Controller is an electronic device that can be used by the Tau to further enhance their connections and control over their robotic companions. A Drone Controller acts as a hub of digital communications between the Drone's operator and any Drones that are nearby the user. It acts as an advanced interface between the operator and the artificial intelligence (AI) combat programs of the Drones, and is often used to direct the Drones’ firepower far more efficiently and with a level of accuracy far greater than would otherwise be possible on the battlefield.
A remarkable feat of Earth Caste engineering, the artificial intelligence of Drones increases when they are networked together into squadrons, greatly increasing their processing speed and capability for independent action. Such deadly squadrons of Drones have no need for Tau controllers and are capable of impressive tactical feats, and operating independently for long periods of time without the need for close supervision. Operating in such a capacity significantly increases the intelligence and processing speed of all the Drones in the squadron through the networking of processing, targeting, and sensor systems, making the whole far more deadly than the sum of its parts. Whilst the most common types of Drone squadrons consist entirely of Gun Drones, in very rare instances entire squadrons have been altered to fit different roles-- such as Commander Shadowsun's usage of Marker Drones to wipe out Ork infantry ensconced in the ruins of the Cha'nel colony.
The Fire Caste combat doctrine, as laid down in the Code of Fire, instructs all warriors to fight closely together, with each member of a team doing his utmost to protect not just his comrades, but also nearby teams in his Hunter Cadre. Using overlapping fields of fire, even Drones are able to provide mutual support on the battlefield in the case of enemy assaults.
So deeply do the Tau believe in the Greater Good, that even their Drones are programmed with self-preservation protocols -- in the face of what the AI deems to be hopeless odds, a Drone will attempt to escape rather than stand and fight. While, at need, Drone Squadrons might be used in high-risk missions or purposefully moved to block enemy paths towards the Fire Warriors, the Tau do not consider Drones to be disposable and the Drone artificial intelligence will analyse every possibility in order to ensure its own survival.
Marker Drones attached to a Tau Stealthsuit Team are always upgraded with stealth field generators, which allows them to operate without compromising the Stealthsuit Team's own ability to remain undetected.
Ordo Xenos Departmento Analyticus Technical Specifications
- Codex: Tau Empire (4th Edition), pp. 25, 31, 35
- Codex: Tau Empire (6th Edition), pp. 32-33, 55
- Imperial Armour Volume Three - The Taros Campaign, pg. 282
- Deathwatch: Mark of the Xenos (RPG), pg. 12