- "The creed is greed."
- —saying amongst Mercs
Mercenary, or simply Merc for short, is a person who takes part in an armed conflict for money. Occasionally they are also hired to hunt down criminals for money.
In the Riddick universe, there is no centralized authority. Instead, the separate sectors of space are generally ruled by whatever entity is the most powerful. This balance of power is in constant flux as different political factions, militant armies and criminal organizations rise and fall in strength. In this ever-changing landscape any true loyalty is unwise for fear that what you pledge loyalty to today will make you a wanted man tomorrow. Thus, mercenaries have entered a new golden age, as it gives soldiers the flexibility to switch loyalties whenever necessary. Mercs generally provide whatever service they specialize in to whoever wants it and is rich enough to pay. Some are soldiers for hire, prison guards or bounty hunters. According to Max Dacher: "Most mercs, they keep it simple: within the law. They do bounty work, the odd war, but they always answer to an organization."
In addition to local governments and corporations, mercenaries are often hired to work aboard larger ships, sometimes for years at a time. How these ships treat prisoners varies depending on the captain. For instance, "plantation vessels" like the Kublai Khan place captured bounties and hired guns alike in stasis, while "slave ships" such as the Dark Athena capture both criminals and innocent colonists for conversion into mind-controlled drones for the highest bidder.