|Engine||Magna 390 XL|
|Communications System||AR-12 Sheathed Directional Beacon|
|Jump Jets||Chevron II|
The Exterminator is a BattleMech that was designed for the most dubious, but necessary, of purposes: headhunting. The Exterminator was outfitted with a special Null Signature System, heat baffles and, in some cases, a Chameleon Light Polarization Shield. These advanced systems allowed it to easily infiltrate enemy lines. Once the Exterminator had breached the enemy's rear, its mission was to find and destroy as much of the enemy's command structure as possible. This mission profile included attacking Mobile Headquarters, field bases and command level officers. Rather than be part of the standard formation, Exterminators were attached to a regimental or higher headquarters unit, often as a fifth member of the command lance itself, before being assigned to individual units. A regiment was considered lucky to have more than one Exterminator, and it was not unusual for its parent unit to pull all assigned Exterminators and pool them for a specific mission.
It was widely believed that the Exterminator had not survived the fighting of the First Succession War as there were lances whose sole mission was to hunt down and destroy this type of 'Mech (coupled with the destruction of General Systems' primary factory on Caph in 2793). In 3007, Kallon Industries (Nanking, Capellan Confederation), looking for a replacement for their aging Wolverine, recovered blueprints for the Exterminator and immediately modified the design so that it could be built using the technology readily available. The result was a BattleMech not only far less effective than the original, but below the capabilities of even the Wolverine it was meant to replace. Only twenty-five of these Exterminators were produced and none survived past the Fourth Succession War, making the design effectively extinct in the Inner Sphere.
Only later was it revealed that the Exterminator still existed in ComStar's private army, the Com Guard, although even here few were of the hyper-advanced stealth models, and while the Exterminator was retained by the Clans its decidedly "dishonorable" method of fighting meant few were used. ComStar continued to produce variants which took advantage of recovered lostech, and the design was used by the Word of Blake during the Jihad.
 Weapons and Equipment
The weapons used by the Exterminator are not nearly as unique or high tech as the electronics on board. The primary weapons of the Exterminator are four Averell Highpoint Medium Lasers, two of each in either arm. For long range engagements, the 'Mech also carries a Deadeye-10 LRM-10 launcher with one ton of reloads in the center torso. These weapons are backed up by a single Dinatech Mark III Small Laser mounted in the head for when engagements close to point blank range, and, for defense against missile attacks, the Exterminator has a Buzzsaw Anti-Missile System in the right torso with one ton of ammo.
For maneuverability the Exterminator carries five jump jets, two of each in either leg and one in its rear torso, allowing it to make leaps of up to 150 meters. Combined with an extralight engine these give the Exterminator the maneuverability of 'Mechs a fraction its size. Ten and a half tons of armor also give it good protection for close-quarters combat while eleven heat sinks provide adequate heat management.
- The 4A is what became of the Exterminator after the Succession Wars, revived by Kallon Industries when they came across blueprints for the design in 3007. The resulting 'Mech resembles the Exterminator outwardly and carries an almost identical weapons load but otherwise is not the same machine. The only weapons change is the use of a M100 Heavy Machine Gun with a half-ton of ammo in place of the Anti-Missile System. A smaller VOX 325 standard fusion engine reduces its top speed by about ten km/h. The armor is still identical to that of the original Exterminator, but unfortunately the Null Signature System could not be saved. This version also made use of a Tek BattleCom communication system and Tek LOR T13d targeting system. BV (1.0) = 1,067, BV (2.0) = 1,345
- The 4C is the fully-equipped stealth version of the 4D and released in the same year, including the Null-Signature System and Chameleon Light Polarization Shield. BV (2.0) = 1,602
- The 5E is a complete upgrade of the Exterminator introduced in 3060 with a new mission of closing with enemy units to deliver improved Narc pods. The 5E has an improved Narc Missile Beacon launcher and all four of its medium lasers upgraded to ER Medium Lasers. The jump jets have been removed from the chassis to make room for an improved C3 computer. To make up for the lack of jumping capabilities, a MASC system has been installed, allowing for an augmented speed of up to 129.6 km/h. BV (1.0) = 1,253, BV (2.0) = 1,532
- This experimental ComStar-produced variant first spotted in 3079 carries a Light PPC in each arm, and a pair of Medium Pulse Lasers as well. An MML 7 with three tons of ammunition in a CASE II protected ammunition bay rounds out the armament. The Anti-Missile System is gone, but in its place are a Chameleon Light Polarization Shield and a Null Signature System. These systems ensure that the 'Mech will be very difficult to hit.
 Custom Variants
- EXT-4DX Exterminator Caine
- The personal 'Mech of Lieutenant Caine Barclay of the SLDF, this Exterminator removed the Null-Signature and Chameleon Light Polarization Shield and as stripping off all of its the weapons. In their place this version carried a MASC and Supercharger, while each arm carried three Medium Pulse Lasers. Each laser was equipped with a Laser Insulator to help diffuse the heat. The anti-missile system was retained, but a smaller engine dropped the cruising speed to 58 km/h. Despite the smaller engine, the MASC and Supercharger allowed Barclay's 'Mech to reach burst speeds of 130km/h. Though Barclay was successful in defeating ten DCMS MechWarriors in duels, the eleventh one destroyed his 'Mech. BV (2.0) = 1,794
 Notable Pilots
- Andery Kerensky, second son of General Aleksandr Kerensky and younger brother of Clan founder Nicholas Kerensky, was a noted Exterminator pilot. 
- Demi-Precentor Rudolf Shakov of the ComGuard's 244th Division notably piloted an Exterminator during the FedCom Civil War. 
- Precentor Krag Jernberg of the ComGuard's 138th Division piloted and died in an Exterminator during the Battle of Tukayyid against Phelan Kell. 
 Design Quirks
The EXT-4DX Exterminator Caine variant has following Design Quirks:
- ↑ MUL online date for the Exterminator
- ↑ Combat Operations, p. 106
- ↑ Technical Readout: 3050 Upgrade, p. 209
- ↑ Technical Readout: 3039, p. 238
- ↑ Technical Readout: 3025 Revised, Exterminator profile
- ↑ Technical Readout: 3050 Upgrade, p. 208, "Produced Exterminator Components on Caph"
- ↑ 7.0 7.1 Technical Readout: 2750, p. 38-39
- ↑ 8.0 8.1 Technical Readout: 3025 Revised, p. 83-84
- ↑ Record Sheets: 3039, p. 150
- ↑ Record Sheets: 3050 Upgrade Unabridged (Clan & Star League)
- ↑ Record Sheets: Operation Klondike, p. 44
- ↑ Combat Operations, p. 123
- ↑ 13.0 13.1 Master Unit List: Battle Values
- ↑ 14.0 14.1 Experimental Technical Readout: ComStar, p. 6
- ↑ 15.0 15.1 Experimental Technical Readout: Gunslingers, p. 6
- ↑ Experimental Technical Readout: Gunslingers, p. 19
- ↑ Technical Readout: 3050 Upgrade, p. 208 "EXT-4D Exterminator"
- ↑ Storms of Fate, p. ??
- ↑ Lost Destiny, p. ??
- Combat Operations
- Experimental Technical Readout: ComStar
- Experimental Technical Readout: Gunslingers
- Master Unit List: Battle Values
- Record Sheets: 3025/3026
- Record Sheets: 3039
- Record Sheets: 3050
- Record Sheets: 3050 Upgrade (Clan & Star League)
- Record Sheets: 3067
- Record Sheets: Operation Klondike
- Storms of Fate
- Technical Readout: 2750
- Technical Readout: 3025 Revised
- Technical Readout: 3050
- Technical Readout: 3050 Revised
- Technical Readout: 3050 Upgrade