Two mercenaries of the Twenty-first Centauri Lancers relax between missions

A Mercenary is a soldier for hire, a warrior who fights not for a particular cause or goal but for material gain. In the Inner Sphere, private, contracted military units have been doing a lot of the fighting. Some are only in it for the cash, some for principle, but, whatever the reason, mercenary forces run the gamut from some the most disreputable to some the most elite troops available. Many mercenary companies do not survive their first battle, but dozens have gone on to become successful, trusted units that form key parts of their employers' defenses.


Mercenaries have played a role in the history of human warfare since the beginning, though there had been a general decline in their use towards end of the second millennium. That changed in the twenty-third century as interstellar exploration and the rise of neo-feudalism created a demand for trained soldiers to fight in what became known as the Age of War. The Reunification War and the formation of the Star League brought about an age of relative peace, again decreasing the demand for hired guns. Mercenaries were still valuable as deniable assets in the Hidden Wars between the Great Houses, but there was little respect for the profession, with many units little more than fly-by-night operations.[1][2][3]

That all changed after the Amaris Civil War. Rather than try to reconstitute the League by force, Aleksandr Kerensky and nearly 80% of the surviving Star League Defense Force chose exile in 2784. Of those SLDF units which remained behind, many hired themselves out to whichever Great House was willing to pay the most for their services. Those services were soon put to the test with the outbreak of the Succession Wars.[2][3] Shortly after it started, the newly formed ComStar created the Mercenary Review Board, a neutral arbitrator for both mercenaries and employers alike.[4]

In their quest to seize the throne of the Star League during the Succession Wars, the Great Houses abandoned the Ares Conventions and committed murder on an unimaginable scale, rendering whole worlds lifeless and erasing centuries of technological progression. Ironically, it was mercenaries who played a role in trying to save humanity from itself, though not necessarily out of noble purpose. Seeking to protect their livelihood, many mercenaries began using their contracts to police their employers, refusing to take missions which violated the Ares Conventions. Mercenaries were responsible for reviving the tradition of offering opponents the chance to surrender and pay a "ransom" so they could return home. Eventually, all factions within the Inner Sphere and Periphery had adopted to one degree or another a code of conduct called the Honors of War. Also known simply as the Conventions, these guidelines were based on the Ares Conventions and mercenary practices which promoted fair dealing and limited warfare.[5][6] And it was a mercenary unit, the Gray Death Legion, which recovered the Helm Memory Core in 3028 and opened the door for the Inner Sphere to start recovering much of the lostech which had disappeared over centuries of constant fighting.[7]

The Clan Invasion was as devastating to those mercenaries caught in its path as it was to the Great Houses which suddenly found themselves the target of the SLDF's descendants: of the 108 mercenary regiments which faced the Clans in front-line combat, nearly a third were totally destroyed.[8] It also revealed the secret origin of Wolf's Dragoons, one of the most celebrated mercenary units in history, as forward scouts for the invasion but who nevertheless chose to side with the Inner Sphere against their Clan brethren. Mercenaries like the Dragoons and Kell Hounds were instrumental in defeating the Clans during the Battle of Luthien, and with trust in ComStar lost after the ComStar Schism the Dragoons helped to create the Mercenary Review and Bonding Commission to replace the MRB. Mercenaries played an important role in the destruction of Clan Smoke Jaguar and ending the Clan threat during Operations BULLDOG and SERPENT, and some went "legitimate" by helping to form a new SLDF.[5][9] In the years after, mercenaries continued to help defend against Clan incursions, but once again soon found themselves caught up in the power struggles of the Inner Sphere: mercenaries fought in the FedCom Civil War, the Capellan-St. Ives War, and operated in the Chaos March region, among other battlefronts.

The Word of Blake Jihad proved devastating to mercenaries: The fight divided mercenaries on both sides. Lots of new units were created, and bigger ones were totally annihilated or went rogue. The end of the war saw Devlin Stone's massive disarmament; the Republic of the Sphere tried to get rid of all mercenaries but only managed to make them scarce. The Dark Age Era saw a new generation of mercenary units, and the conflicts of this era gave them plenty of work.[10]

The beginning of the IlClan Era saw another explosion of mercenary work, especially in the Hinterlands, where several proto-states were born, contracting all the mercenary units they could find.[11] In the same era, the mercenaries worst problem was the growing ineficiency and corruption of the MRBC, but they soon found an unexpected successor: Clan Sea Fox became quickly a reliable bonding agent once Fox Khanate began intermediating as a broker between mercenaries and clients.[12]


Mercenary units come in all shapes and sizes, though for the most part conforming to standard Inner Sphere military structure. Most employ BattleMechs, not least because these units get the most "bang for their buck" in terms of versatility and ability to accomplish a variety of missions, but others may instead employ other units like Combat Vehicles or Infantry. However, few mercenary formations will utilize just a single unit type, as each has its own important role to play in the completion of the mission and the formation's survival. Even a single 'Mech Lance operating on its own can expect to employ a number of scouts necessary for performing reconnaissance or sabotage missions and support personnel to keep their machines working.[13][14][15]

Most successful 'Mech mercenary units employ a variety of different weight types and mission profiles in order to maximize their fighting potential. Depending on where they originated some units will feature designs associated with that region of space (e.g. a unit from the Free Worlds League might have more Trebuchets than typical), but given the nomadic lifestyle and reliance of salvage this does not necessarily hold true. Most units lack the resources to buy the latest designs available to House forces, and with few exceptions don't have the technical knowledge to salvage Clantech, instead selling captured examples to the Great Houses in exchange for Inner Sphere equipment. Many will include a fair number of conventional assets attached to support the 'Mech forces, whether it's swift hovertanks spearheading an assault, VTOLs scouting the enemy's position, Jump Infantry performing anti-'Mech attacks or special forces operating deep behind enemy lines.[14][15] Some units such as artillery and conventional fighters are less common among mercenary commands yet still find a place in their ranks. Perhaps the most rare are Land-Air 'Mechs, with only the wealthiest able to maintain even a handful of such machines.[13]

Mercenaries make a point of securing their own transport, as to do otherwise requires relying on the good graces of their employers. Many own their own DropShips, preferably enough to carry the entire formation, allowing them to make planetary assaults and retreat from losing battles of their own volition. Having to hire out for DropShip transport can quickly get expensive: chartering a single Union for a one-jump trip in 3059 could cost 150,000 C-bills, more if multiple jumps are involved.[16] However, the rarity and expense of JumpShips means only the most successful mercenaries are able to purchase one for their use. For everyone else, the standard rate in 3059 of 50,000 C-bills per DropShip per jump is one cost they must bear.[16] On the other hand, most mercenaries give a low priority to employing aerospace fighters, generally seeing them as a poor return on their investment and more willing to rely on their employers to provide aerospace support, though even the most 'Mech-oriented mercenary commander will include some in their organization.[13][14][15]

Perhaps the most important part of a mercenary formation are the support and administrative personnel which help keep it going: those commanders hoping for long-term success will recruit a technician as vigorously as they would a MechWarrior. Many mercenary formations cannot afford a support staff large enough to cover 100% of their needs, but will ensure a majority is kept in-house to avoid having to rely too heavily on expensive outside support.[14][15] Ideally, each 'Mech or fighter will have its own technician assigned to maintain it, with assistant technicians to assist them (at least one Astech for every two Techs), but not every mercenary formation is so lucky.[17][18] Mercenaries also try to maintain a ratio of one medical personnel for every twenty, though whether these are simple paramedics or full surgeons will depend on what they can afford.[19][20] Other important administrative positions include secretaries, accountants, and contract negotiators; smaller commands will often have officers or NCOs pull double-duty in these positions, but those which can afford their services benefit greatly from having a dedicated support staff.[19][20]

The Business of War[edit]

How mercenary commands are created varies tremendously. Often they might be the remnants of a defeated army looking for a new purpose, or members of a professional force who desert on account of political or economic differences with their leaders.[2] On occasion, a Great House might purposefully create a mercenary command out of its own units to serve as a deniable asset...with the risk that these "mercenaries" might turn their fictional status into reality and go independent.[3] For most soldiers of fortune though, their choice to turn mercenary was not out of greed or nobility but a desire for freedom, whether it's the freedom to be their own boss or freedom from social conventions.[21] Often a mercenary unit is founded by a charismatic officer and their core group of supporters - such as family members or friends made at the academy - going out and recruiting new members and purchasing what equipment they need to form their unit.[22][23]

Keeping a mercenary unit running requires securing a profitable contract, which can be difficult at times: with variations in interstellar travel and politics, a mercenary command might be lucky to work eight months out of the year.[24] While many worlds can be said to operate a Hiring Hall where mercenaries and prospective employers can meet to arrange business, only certain planets have a reputation for offering steady work and the best mercenaries money can buy.[25] For many years Galatea was the premier mercenary hiring center, the original Mercenary's Star, though it has since had to share that honor with Outreach and the rise of the Dragoons' MRBC.[26] Other planets which have operated hiring halls at one time or another include Solaris VII, Arc-Royal and Northwind.

The types of contracts which might be available can run the gamut of military and covert operations: training militia units, pirate hunting, conducting planetary invasions, assassinations, reconnaissance, objective raids, and counterinsurgency to name a few. The best types are those which are specific in the rights and obligations of both employer and mercenary, and hashing out the particulars is an important role for the negotiators on both sides. One point of negotiations is how long a contract will last, whether a single month to conduct a raid or a retainer agreement for at least a year or more.[27] Command rights are another important point, with a mercenary unit operating fully autonomously at one end of the spectrum to fully integrated into the employer's armed forces at the other. Transportation is also a major sticking point, as mercenaries do not want to be fully reliant on their employer to get to (and more importantly get out of) the mission location, while employers who lack transport of their own might have to reimburse mercenaries up to half the cost of using commercial transport. Salvage rights can sometimes make or break a contract, with mercenaries preferring to keep as much as they can get while employers often seek ways to recoup some of the cost of hiring mercenaries. How much an employer will reimburse a mercenary's technical support also plays an important role in the contract: some employers might pay a straight percentage cost of the tools, materials, and salaries of the technicians, or cover a specific percentage of battlefield losses under a battle-lose compensation arrangement. Finally there is the question of remuneration, the out-of-pocket expenses such as starport taxes or food purchases, though typically these expenses are minor and rarely worth haggling over.[27][28][29]

Once a contract is secured, ensuring the rest of the formation gets paid is just as important. Many commands pay their mercenaries on a monthly salary basis, with the risk that repeated failure to pay can cause some to quit or change sides.[30] These salaries are also kept as low as possible in order to keep expenses down: one of the highest paid soldiers in a mercenary command, a MechWarrior, in the middle of the thirty-first century could expect an average base salary of just 18,000-19,000 C-bills a year (though veterans and officers could expect several times that amount).[31][32] Alternatively, some commands operate on a profit-sharing scheme, eliminating the problem of monthly salaries, but with the added issue of making each member of the command an "investor" in the enterprise with voting rights on matters such as leadership.[30]

Just as important as paying mercenaries is making sure their equipment keeps running, which is where many commands have run into problems. A single 'Mech can require up to 60 man-hours of maintenance a week, not including battle damage repairs.[31][33] Finding replacement parts and ammunition requires a degree of planning and forethought, as not every planet is going to be stocked with exactly what may be needed. Ideally a mercenary commander will have agreements set up with private contractors to provide a steady stream of supplies, but such agreements can quickly eat into profit margins. Many employers are also unhappy with such arrangements, whether because it makes the mercenaries too independent or opens a hole for sensitive intelligence to leak, and often put up roadblocks. Alternatively, a commander can agree to get supplies directly from the employer to lower expenses and increase margins, but with the additional risk of falling prey to the Company Store trap.[30]

In the end, an average mercenary command might earn several million C-bills in a year, but with all the expenses associated with the mercenary lifestyle that money can evaporate in a flash.[34] If a command gets into debt badly, it's very hard to get back into the black. Most financial institutions are loath to lend money to mercenaries and add significant markups when they do: offering collateral equal to the cost of the loan can secure a "low" interest rate of 25%.[35] Given the dangers to mercenary commands both on and off the battlefield, it is no surprise then that many will meet ignoble ends. By one statistic, forty percent of all new mercenary commands are destroyed or dissolved within the first six months of their forming; sixty percent of those who make it past this point will suffer the same fate within their first year.[36]

List of Notable Mercenary Units[edit]

Countless numbers of mercenary formations have come and gone over the centuries, but a few have made a notable mark and become famous (or infamous) for their exploits. For a full list of all known mercenary units, see Mercenary Commands.

Eridani Light Horse
Eridani Light Horse logo 3062.jpg
One of the oldest and most prestigious mercenary commands, the Eridani Light Horse was originally part of the SLDF as the Third Regimental Combat Team. One of the few SLDF units to turn mercenary and maintain itself during the Succession Wars, the ELH was later instrumental in turning back the Clan threat and helping to reconstitute the second Star League. Destroyed in the Jihad, they were reborn in the IlClan Era.
Kell Hounds
Kell Hounds logo.png
The Kell Hounds have played a historic role in course of events since their founding in the early part of the thirty-first century. They were one of the first Inner Sphere units to encounter the Clans, and from that meeting Phelan Kell joined Clan Wolf. They helped turn back the Clan Invasion, and in partnership with Clan Wolf-in-Exile created the Arc-Royal Defense Cordon to defend against further incursions. Almost annihilated by Malvina Hazen, they barely remained operational. In the IlClan era, after liberating Arc-Royal from the Jade falcons, they founded the Arc-Royal Liberty Coalition with them as their mainstay force.
Wolf's Dragoons
One of the most storied mercenary units in history, Wolf's Dragoons were secretly members of Clan Wolf sent to spy on the Inner Sphere in preparation for the Clan Invasion. However, the Dragoons would eventually decide to switch sides and help the Inner Sphere, playing an instrumental role in defeating the Clan threat. From their homeworld of Outreach they created the MRBC and the Allied Mercenary Command to counter the threat posed by the Word of Blake. Almost annihilated in the Jihad, they rebuild most of their forces along to a century. Betrayed and almost destroyed in Terra, they began rebuilding again in the IlClan Era.
Northwind Highlanders
The Northwind Highlanders were a mercenary unit under exclusive contract to House Liao until the Fourth Succession War, when they sided with House Davion in return for their ancestral home of Northwind. They served the Federated Commonwealth in beating back the Clan threat, but eventually gained independence for themselves, joining with the Allied Mercenary Command in opposition to the Word of Blake. After the Jihad, they joined the Republic of the Sphere, abandoning mercenary service. With the end of the Republic, they resumed mercenary service again.
McCarron's Armored Cavalry
McCarrons Armored Cavalry logo 3076.png
McCarron's Armored Cavalry was one of the largest and most successful mercenary units. Under exclusive contract with House Liao for much of its existence, the Big MAC went above and beyond in help to ensure the survival of its employer. The unit was eventually rewarded for its service by being formally incorporated into the CCAF and its soldiers made full citizens of the Confederation.
Gray Death Legion
Gray Death Legion logo.jpg
The Gray Death Legion was formed by Grayson Carlyle in the aftermath of his father's death. Against impossible odds the young Carlyle grew the Legion into a formidable fighting force, and was responsible for a technological renaissance with the recovery of the Helm Memory Core. The unit did not long outlive its founder, being destroyed in the FedCom Civil War, though the survivors would found Gray Death Technologies. The unit was reborn in the ilClan Era by hands of Grayson's descendants.


  1. Era Report: 2750, p. 154
  2. 2.0 2.1 2.2 Mercenary's Handbook, p. 7
  3. 3.0 3.1 3.2 Field Manual: Mercenaries, p. 7
  4. ComStar, p. 15
  5. 5.0 5.1 Field Manual: Mercenaries, p. 8
  6. Mercenary's Handbook, p. 29
  7. Technical Readout: 3039, p. 222
  8. Field Manual: Mercenaries, p. 26
  9. Field Manual: Mercenaries, Revised, p. 7
  10. Field Manual: 3145, pp. 176–177
  11. Tamar Rising, pp. 82–88
  12. Riptides
  13. 13.0 13.1 13.2 Mercenary's Handbook, pp. 8–10
  14. 14.0 14.1 14.2 14.3 Field Manual: Mercenaries, pp. 26–28
  15. 15.0 15.1 15.2 15.3 Field Manual: Mercenaries, pp. 30–32
  16. 16.0 16.1 Field Manual: Mercenaries, p. 157
  17. Field Manual: Mercenaries, p. 30
  18. Field Manual: Mercenaries, Revised, p. 35
  19. 19.0 19.1 Field Manual: Mercenaries, p. 147
  20. 20.0 20.1 Field Manual: Mercenaries, Revised, p. 150
  21. Field Manual: Mercenaries, p. 10
  22. Field Manual: Mercenaries, 135
  23. Field Manual: Mercenaries, Revised, p. 137
  24. Mercenary Handbook, p. 11
  25. Field Manual: Mercenaries, Revised, p. 11
  26. Mercenaries Supplemental, p. 10
  27. 27.0 27.1 Mercenary Handbook, p. 19
  28. Field Manual: Mercenaries, pp. 32–34
  29. Field Manual: Mercenaries, Revised, pp. 26–28
  30. 30.0 30.1 30.2 Mercenary's Handbook, pp. 11–12
  31. 31.0 31.1 Field Manual: Mercenaries, p. 146
  32. Field Manual: Mercenaries, Revised, p. 148
  33. Field Manual: Mercenaries, Revised, p. 149
  34. MechWarrior: The BattleTech Role Playing Game, p. 105
  35. Field Manual: Mercenaries, Revised, p. 181
  36. Field Manual: Mercenaries, p. 9