Mercenary

A mercenary is an armed combat specialist who hires out his or her services for the sake of profit. Most mercenaries hail from a military background and are usually skilled in multiple fighting techniques such as hand-to-hand combat, firearms, aerial combat, vehicular combat, etc. Some mercenaries may also employ themselves as bounty hunters, collecting reward money for capturing escaped refugees. By and large, the most effective mercenaries are of low moral character and have no compunctions against taking the life of a living being if the mission calls for it. Ultimately however, their actions and allegiances are almost always prioritized by how much they are getting paid for their services.

In film

 * Species: The government hired a mercenary named Preston Lennox to assist a scientific team in tracking down a murderous alien/human hybrid named Sil. After following a trail of bodies, Lennox found Sil in a sewer where he killed her blowing her head off with a grenade launcher.