Sometimes occupation of a sector of a MADDS defended planet is unavoidable. Even the most vigilant and efficient computer systems can't possibly account for every single contingency in existence; they simply determine the most logical or probable ones and take measures against it.
When the occupation becomes a reality, MADDS takes actions against letting such bulkheads grow in size and strength, and ensuring that supply lines are disrupted and enemy forces pinned, until such a time that a substantial force can be rallied and the site of occupation can be effectively neutralized.
A key ingredient in keeping these occupations under the ever watchful eye of MADDS is the OD-RSDs, the Orbitally Deployed Recon and Sabotage Drones.
OD-RSDs come in teams of four, and are deployed in a single Drop Pod, from a mid-orbital MADDS skybase. The pod is large, about two tonnes in weight (a relatively light weight orbital insertion device though) and enters the atmosphere at a shallow angle. Once in atmosphere, it catapults itself down to earth, implanting itself as close to the occupied region as possible. Once the insertion is complete, the pod opens and the OD-RSD Drones emerge. Needless to say, a flaming piece of metal entering orbit usually arouses some suspicions, so the drones do their best to flee from the scene of the drop as soon as possible and make their way to the target.
OD-RSDs look alot like skeletal, specters of drones. They have little to no exoskeletal armor, and are instead covered by a sheath of light carbon fiber. This is no ordinary carbon fiber metal, it's inlaid with millions of chameleon cells (not from the actual animal, mind you) - synthetic cells bonded with a light-reflecting compound, which when ionized, reflects or refracts light to effectively bend it in such a way that it simply glides over the drones form, making it invisible to the naked eye.
This is particularly useful considering that A) Humans can only see the visible spectrum and B) Organic Drones default to scanning the visible spectrum, unless provoked. While Mecha and other drones may scan the thermal and ultraviolet spectrums for activity, the OD-RSD drones sport a miniature cold-fusion reactor, leaving their thermal signatures as unassuming,albeit anomalous, blips on the thermal radar.
Optimally however, the drones will never meet said opposition at all. Their entire chasis has been designed for stealth. Hydraulic legs move without a sound, and servos have been outfitted with a number of dampeners to eliminate their electronic wizzes and humms. The drone can maintain speeds in excess of thirty miles per hour, making it one of the fastest land-speed drones in it's weight class. It's agility and silence is what makes it adept at recon and sabotage.
The primary function of the Drone is to bring dark areas that have been either shut down completely, or occupied, back onto MADDS' radar. This is done by careful placement of Echo-radar emitters, devices that emit a high pitched sound, that it uses to shape an image of the land. Triangulating these devices throughout a sector can create a fairly precise 3d geographical image. This image is sent back up to MADDS by a secure remote connection, established by the team of OD-RSDs. Secondly, the Drones establish a series of thermal and acute tremorsensors around enemy encampments. These sense both heat signatures and vibrations in the ground. While they do not give a clear or distinct image, enemy activity and numbers can be monitored by studying the heat signatures and the amount/quality of terranean activity.
Each of the four drones can stream data through onboard sensors to MADDS, though this is obviously limited to whatever it's sensors can detect at one time.
The OD-RSD's primary objective is not engagement, but recon. If engagement is imminant, the first protocol for the drone is to flee and regroup. However, the drone does have some defensive capability. Using it's stealth ability, the Drone can strike from seemingly anywhere, using sharpened carbon-fiber claws to shread through light armor and dermal plating (and of course, flesh.)
Ranged weaponry is limited to a single shot, wrist mounted "Whisper Cannon" which shoots a projectile at high velocity along rails, silently. The round is armor piercing, and guided. A guidance chip is included in the round, which can manipulate very small fins on the back of the bullet to makem inute adjustments to account for wind or the turning of the earth. Needless to say, this weapon is not effective in gunfights, but functions ideally for stealthy, single-target takedowns or quick escapes.
Then of course is the thermo-nuclear charge. The drones are, at the end of the day, programmed in both recon and sabotage. Thermonuclear charges can range in size and shape, but no matter what the blast is magnificent. A controlled blast might be as small as necessary to rip apart a single compound, and nothing else, or as large as to wipe an entire colony from the face of a planet. Aided by their chameleon "skin" the drones have little issue planting these devices in the cover of night, so long as they can stray away from the prying eyes of electro-magnetic sensors.
Dealing with OD-RSD threats
The best way to get rid of OD-RSDs is to track the descent of space debris, and make sure every report is investigated quickly. The OD-RSDs are helpless inside their pod, and if one can destroy the pod with them in it, it nullifies most of the danger.
However, when that ceases to be an option, the best form of protection is constant vigilance. A good start is determining whether OD-RSDs have breached your perimeter. Looking for an empty pod on the outskirts of a sector is always a good indicator that you might be under MADDS surveillance or, worse, at risk of being the victim of a thermonuclear detonation.
Thermal detection methods work up close, though being too close to an OD-RSD could just as easily mean death if you stray too near. The best detection is to set scanners to sniff out electromagnetic signatures, which all drones give off. Once spotted, the drones have only their legs to help them flee, which, no matter how formidable a run speed they can maintain through woods or across flat land, can not outrun airborn drones or, for that matter, missiles. With no explosive plating or even small-arms protection, exposed OD-RSDs are veritable lambs to the slaughter.