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Mercenaries are professional soldiers hired to perform a variety of jobs. In modern times, most mercenaries come from groups called Private Military Corporations. Mercenaries in any game can come from any background whatsovever but it is mostly some kind of military background such as the US Army or unconventional groups such as the Irish Republican Army.
Mercenaries make up the human enemies in Far Cry. Hired by Dr. Krieger to protect the island from outsiders and under the command of Colonel Richard Crowe, these ruthless mercs are trained to take out any intruders as quickly as possible. To make their job easier, mercs are equipped with high-tech weapons and equipment, such as the OICW and G36. They also use vehicles such as boats and Jeeps to ensure that every route to and on the island is sealed off.
Theses mercenaries are known to be the most ruthless of their kind since they fully understand their employer is a mad scientist who uses human test subjects.
Some mercenaries have been assigned to make sure that the Trigens are under control and to protect the scientists. Ironically however they tend to be killed by Trigens unless they have the high ground, are well equipped, in larger numbers or they are a good distance away from the Trigens.
While their exact number is unknown it appears there are at least over 1000 mercenaries working for Dr. Krieger on the archipelago. The majority of this mercenary army is made up of American soldiers, however other nationalities included seem to be Australian and French judging from a couple of conversations, though it is likely there are more. Due to the archipelago's location (noted by Dr. Krieger as being "isolated") intruders are rare, thus the mercenaries rarely get into combat, with some resenting this and in a few cases even wishing for some action. Dolphin and shark hunting is one way mercs pass the time. This does not mean they are ineffective though, as they train regularly.
In order to keep Dr. Krieger's research from being discovered the mercenaries use short range radios to communicate with each other instead of using cell phones (as cell phones use satellites that could be traced). A main communications facility built into an old fort in the middle of the archipelago allows all mercenaries and islands to stay in contact. Apart from this means of communication the mercenaries can not use the Internet or e-mail and are not allowed to leave the islands. They are also forbidden to talk about Krieger's activities. However those posted on the outer islands tend to know less about the experiments than those located nearer anyway. Every single person, mercenary or otherwise has a locator chip implant to allow Dr. Krieger (and presumably Crowe as well) to keep track of all movement. Called an LSI by Doyle, who also calls the signals "locator signals", it probably stands for Locator Signal Implant.
There are two groups of mercenaries, the regular forces that mainly patrol the outer islands and the elite mercenaries, who are responsible for guarding vital areas and keeping the Trigens under control. Regular mercs who perform well may become elites and receive better equipment. Both groups use attack helicopters and other vehicles to deal with any threats as well as a variety of weapons thanks to Krieger's funding.
It is obvious from mercenary dialogues that the majority (if not all) of the mercs have a strong disliking for their leader Richard Crowe, doubting his ability to command the merc forces and his attitude towards his men. However most would be reluctant to say this to his face.
Far Cry 2
Mercenaries in Unnamed African Country (UAC) are mostly under the employment of the two warring factions, the United Front for Liberation and Labour and the Alliance for Popular Resistance. These mercenaries make up a large portion of these groups and are a big reason for their success but usually hold no concern for the groups themselves considering they are just guns for hire. They can come from all different nationalities, most of them presumably from countries with major military backrounds, such as Russia or Burma. Mercenaries found in UAC can come from any background, such as ex-Provisional IRA gunmen Frank Bilders, Kosovo Liberation Army guerilla Josip Idromeno, and even the office clerk Paul Ferenc. Many Mercenaries in UAC are also under the employment of The Jackal either to guard weapon dumps or weapon deals or dealers that are under his employment. Initially Mercs were equipped with weapons such as the G3KA4 and Homeland 37. Eventually, they begin to use better equipment such as FALs, LMGs, and will even use mortars.
Far Cry 3
The Mercenaries in the Rook Islands are the Privateers. They are led by Hoyt Volker are the human enemies on the Southern Island. Their motives on the Rook islands are to protect and oversee Hoyt's various operations based on the islands. It should be kept in mind that Hoyt himself is not a mercenary nor is a part of them, he merely hires them for his business.