Riordan Dynamic Weapon Systems combines the best of weapon design in the Advanced Plasma Rifle v23, commonly known as the Link Gun, or simply the Link. While the primary firing mode of the Link remains the same as its plasma-firing predecessor, the secondary cutting torch has been replaced with an active-scanning, switchable energy matrix. This matrix enables the weapon to register friend or foe upon contact with the swirling green beam and change properties accordingly. When the beam comes into contact with an opponent it can inflict serious injury and death within seconds. Upon contacting a teammate, it reverts to a harmless carrier stream. The carrier stream offloads energy from the onboard cells, boosting the output of any targeted player who is also using the Link. Two players may link to one another at any time, boosting the power output of the weapon significantly, but it should be noted that while players are boosting a teammate, they are unable to defend themselves from attack. -- Official description

The Link Gun serves several purposes, not all offensive.

The primary firing mode sends out several balls of plasma that travel fairly fast in a straight line. It is fairly damaging, but you should be close to your enemy, otherwise they have a very good chance of getting out of the path before the balls connect.

The secondary fire mode is what you will be using most of the time. When used against enemies, it emits a long beam of plasma that has good range, and is continuous. If you can keep the enemy targeted, the beam will continually hit them, as long as you don’t get out of range. It isn’t as damaging as the primary mode, but it still gets the job done.

In Onslaught games, the alternate fire can be used to speed up the construction of power nodes, repair power nodes, and repair vehicles. When you use the alternate fire on a teammate who is also using the Link Gun, you can boost the power of the teammate’s weapon for as long as your ammo holds up. This can be done for multiple teammates, essentially creating a large chain (or, as the name says, link) of players, all powering up.