Production information
Manufacturer Achernar BattleMechs[1]

Defiance Industries

Kallon Industries[1]

Production Year 2777[2][3]
Model ENF-4R[1]
Class Medium
Cost 3,536,875 C-bills
Technical specifications
'Mech type Inner Sphere BattleMech
Mass 50 tons
Chassis Dorwinion Standard
Armor Starshield
Engine Nissan 200
Communications System Achernar Electronics HICS-11
Targeting Tracking System Federated Hunter
Heat Sinks 12 single
Speed 64 km/h
Jump Jets McCloud Specials
BV (1.0) 895[4]
BV (2.0) 1,032[1][5]


Since it first walked off of the production line, the Enforcer has been the iconic medium-weight workhorse of the Federated Suns' Succession Wars era military. This is in large part due to production of the Enforcer remaining largely undisturbed throughout the Succession Wars, despite the relative lack of industrialization that has long hampered the Federated Suns. With the autocannon-obsessed Armed Forces of the Federated Suns building up its BattleMech forces upon the collapse of the Star League, the discovery on Achernar of schematics for an unbuilt autocannon-carrying Star League 'Mech was a case of perfect timing. Modifying the design by swapping two medium lasers for a single larger one, Achernar BattleMechs rushed it through development and began production in 2777.[2][3]

The Enforcer fulfilled the roles of a mobile barrage vehicle, laying down an intense hail of fire as a prelude to an offensive or to blunt an enemy's attack, and as a trooper 'Mech, using its thick frontal armor and good jumping distance of 120 meters to effectively brawl with the enemy despite lacking hand actuators. The sturdy and inexpensive design's mobility also made it an ideal city fighter, especially when sniping the enemy during hit-and-run attacks. One of the design's problems was that, with most of its nine tons of armor concentrated forward, the amount of protection in its rear torso is less than on some light 'Mechs. The Enforcer's biggest flaw was its limited ammunition stores, though somewhat mitigated when a truck-and-crane reloading system is used during less-mobile battles. Attempts were made to replace the small laser with another ton of ammunition, however there were complicated linkage problems in getting the ammo from the left torso to the right arm, increasing the rate of jamming or reducing the rate of fire to unacceptable levels. What's more the rounds had to be routed along the 'Mech's back where its armor was weakest.[2][3]

The Enforcer was given extra prominence by the Federated Commonwealth. The alliance between the Lyran Commonwealth and Federated Suns resulted in Defiance Industries obtaining the designs for the 'Mech to build at their Hesperus II plant,[6] allowing the nascent AFFC to emphasize the pairing of traditionally Federated Suns 'Mechs like the Enforcer and Valkyrie alongside Steiner standards like the Zeus and Commando, especially in the Federated Commonwealth Corps.[7]

As many of the secrets of lostech were recovered by the NAIS, Achernar brought in many veteran Enforcer MechWarriors to help them design the newest model, the ENF-5D. This variant became the standard medium 'Mech for the Federated Commonwealth when it debuted in late 3050, and the Armed Forces of the Federated Commonwealth immediately contracted the entire Achernar line for a 10-year run. The AFFC distributed the new 'Mechs to key formations including the Davion Brigade of Guards, Royal Guards and FedCom Corps, and bought up Achernar's upgrade kits for other distinguished units. However, demand for the new Enforcers during the Clan Invasion out-stripped Achernar's ability to supply them, requiring First Prince Hanse Davion to order that Kallon Industries be granted a license to produce Enforcers. Both companies would continue to produce Enforcers through the next 20 years until the Jihad, when Kallon Industries' plant on Talon, moon of Wernke, was destroyed in 3069.[8][9] The Jihad would also end Enforcer production at Defiance Industries.[10]

Weapons and Equipment[edit]

The Enforcer's primary weapon is a Federated Autocannon AC/10, an excellent large-caliber model firing in bursts of 10 rounds and whose cooling jacket doubles as a protective sleeve for engaging in hand-to-hand combat. While one ton of ammunition only allows for 10 bursts total, the rounds are stored in an equivalent number of big clips which are easy to eject and reload. Complementing the autocannon is a ChisComp 43 large laser in the left arm, both giving the Enforcer respectable intermediate range firepower, while a ChisComp 32 small laser in the left torso provides for close range combat.[2][3][11]


  • ENF-5D 
    First walking off the production line in late 3050, the 5D Enforcer is a major upgrade to the standard 'Mech, meeting many of its pilots' desire for something faster, better protected, and with more endurance. The Nissan 200 engine has been removed and replaced with a Magna 250 extralight engine, increasing the Enforcer' top speed to 86.4 km/h and the amount of space available for other additions. The armor has been stripped from the 'Mech and replaced with StarGuard CIV ferro-fibrous armor with CASE to protect against an ammunition explosion while the weapons payload has also been changed. Retaining the small laser, both the AC/10 and the large laser were replaced with a new Mydron Excel LB-X AC/10, fed by two tons of ammunition, and a BlazeFire Sweetshot ER large laser. Finally, an additional jump jet was added, increasing the jumping distance by 30 meters, up to 150 meters, to keep up with the Enforcer's new speed profile. BV (1.0) = 1,093,[4] BV (2.0)= 1,308[9]
  • ENF-5R 
    Introduced after the fall of New Avalon to the DCMS during the Dark Age, this Enforcer variant was produced by Kallon Industries to quickly replenish the depleted ranks of the AFFS. It uses a 200-rated light engine to improve survivability when compared to the ENF-5D, though the top speed is reduced to 64 km/h with a jump radius of 120 meters. It uses the LB 10-X autocannon of the 5D, but the left arm mounts a large re-engineered laser for use against special armor types, while an ER small laser is mounted in the left torso. Two tons of ammunition is carried in a CASE II protected bay in the right torso, and ferro-fibrous armor provides protection..[12] BV (2.0) = 1,192[13]

Custom Variants[edit]

  • ENF-5D Daniel 
    While the body of his 'Mech was factory refitted to the 5D standard after the initial Clan Invasion, Waylen adopted a more modern version of its War of '39 weapons loadout, carrying a now refined Gauss rifle, two ER medium lasers in the left arm and a single torso mounted ER small laser.[15]

Apocryphal Variants[edit]

Apocryphal Content Starts

The information after this notice comes from apocryphal sources; the canonicity of such information is uncertain.
Please view the reference page for information regarding their canonicity.

From MechWarrior Online:

  • ENF-5P 
    A departure from the normal autocannon and laser Enforcer, the 5P mounts an UAC/5 in each arm with two total tons of ammunition and a single small laser in the left torso. Two jump jets mounted in each side torso coupled with 12 total double heat sinks round out its equipment, running off of a 250-rated extralight engine housed by standard internal structure components and 12 tons of standard armor.
  • ENF-GH Ghillie 
    The MWO Hero 'Mech version of Daniel Waylen's personal Enforcer, the Ghillie enhances the sniper nature of his custom variant with the addition of a Guardian ECM suite.[16]

Apocryphal Content Ends

Design Quirks[edit]

The Enforcer is subject to the following Design Quirks:[17]

Related BattleMechs[edit]

  • Watchman - Derived from the Star League prototype for the classic ENF-4R, the lighter Watchman was designed as low-cost replacement of the END-5D for use as a training and garrison 'Mech for planetary and march militias. The Watchman possesses a fusion engine, and mounts a large laser, a pair of medium lasers, and a pair of machine guns. The large parts commonality between the Watchmen and 4R Enforcer ensures a ready supply of spares to maintain them in operation.[18]
  • Sentry A revision of the Watchman, with superior anti-infantry capability and incorporating more advanced technology than its predecessor. It, too, was designed for maximum compatibility with the previous 'Mechs and distributed widely within the Federated Suns[19]
  • Cuirass Another Watchman-derived 'Mech; the Cuirass is designed as a light skirmisher to complement the Legionnaire. It unfortunately struggles to make the best use of its mobility and weapons loadout due to its outdated heat sinks.[20]


  • The Enforcer and Enfield have very similar weapon loads and combat roles. Additionally, plans for both BattleMechs were discovered on Achernar, although the Enfield was discovered nearly 100 years later in 2870. Whether there is any connection has never been officially addressed.[22][23]
  • In German products, the unit's proper name was translated to Vollstrecker. The model code was accordingly changed to VOL-4R.
  • In French products, the unit's proper name was translated as Exécuteur.



  1. 1.0 1.1 1.2 1.3 Technical Readout: Succession Wars, pp. 82–83: "ENF-4R Enforcer"
  2. 2.0 2.1 2.2 2.3 Technical Readout: 3025, p. 56
  3. 3.0 3.1 3.2 3.3 Technical Readout: 3039, p. 134
  4. 4.0 4.1 Combat Operations, p. 127
  5. Record Sheets: 3039, p. 123
  6. NAIS The Fourth Succession War Military Atlas Volume 1, p. 42
  7. 20 Year Update p. 17, Defense Industries
  8. Technical Readout: 3050, p. 110
  9. 9.0 9.1 Technical Readout: 3050 Upgrade, p. 56
  10. Objectives: Lyran Alliance, p. 29, Defiance Industries
  11. Classic BattleTech Introductory Record Sheets, p. 12
  12. Recognition Guide: ilClan, vol. 18, p. 13
  13. Recognition Guide: ilClan, vol. 18, p. 19
  14. Starterbook: Sword and Dragon, p. 23, 94
  15. Starterbook: Sword and Dragon, p. 107
  16. MechWarrior Online Resistance Heroes Sale Page
  17. BattleMech Manual, p. 91 - Design Quirk Table - Enforcer Entry.
  18. Technical Readout: 3055, pp. 34-35
  19. Technical Readout: 3060, pp. 86-87
  20. Technical Readout: 3085: Supplemental, pp. 26-27
  21. Technical Readout: 3060, pp. 96-97
  22. Technical Readout: 3058, p. 108
  23. Technical Readout: 3058 Upgrade, p. 134