The Scourge Project is a third-person shooter set in the near future, where players assume the role of the Echo Squad, a group of specialized mercenaries under the orders of Tarn, a dissident faction that is trying to unmask the strange experiments and businesses of the Nogari Corporation, a company that has exclusive control on the production of Ambrosia, a new form of energy that has replaced the already exhausted traditional power sources.

The mission in the game is to rescue Dr. Reisbeck, a double agent that has been able to infiltrate the company's facilities in the Island of Nogari and retrieve a sample of a meteorite that the corporation keeps heavily guarded, which is suspected to be the original source of Ambrosia.

During the course of the game players can choose to control any of the four characters that are part of the Echo Squad: Stonewall, Shade, Amp and Mass. They all have a different point of view of how the story develops, each having a unique set of flashbacks that will determine their intentions and objectives. Each one of them has also a combination of special abilities that are different from their teammate's, which will change the game experience depending on the chosen character.

In the campaign menu there are three game modes:

Single player: control a specific character and the rest of the team will be managed by the computer's AI.
Co-op: in this mode players can go online, each one of them playing the role of one of the four different team members.
Action mode: the player controls one character only, without the rest of the team. In this mode there are no flashbacks or any story elements of the adventure, just pure action in the different settings of the game.

In the multiplayer mode there are several additional maps, where it is possible to play Deathmatch, Team Deathmatch, Capture-the-Flag and Frontiers' games with up to sixteen players.

The game has an order system (QOS Quick-Order-System) through which players can give basic instructions to the teammates, whether they are real players or AI controlled players. There is also an experience and medal system that gets updated as players advance through the Campaign and Multiplayer modes.