In the campaign additional parts, weapons, and ammunition are acquired through the missions, captured supplies, and salvaged enemy Mechs.

Also in the campaign, the player controls up to three squadmates, with the ability to issue basic orders such as attack, move, and return to the Mobile Field Bases (MFBs) for repairs.

As Mechs do not have shields, and are only protected by armor which is damaged in combat, the MFBs can become crucial in enabling the player to complete a mission.

The remaining four survivors gradually link up over the course of the game, and learn of the overwhelming success of other Inner Sphere forces across Smoke Jaguar territory from intercepted Clan communications.

Despite this setback, the player must continue with his remaining objectives, hoping that a Clan shuttle can be obtained from the spaceport in order to escape.

After completing all objectives and reaching the spaceport’s landing fields, the player is finally confronted by and kills Brendon Corbett in an honour duel for the remaining shuttle.

Having ended any hope of a Smoke Jaguar rally on Tranquil, the player’s mechs depart and rendezvous with the Eclipse in orbit.

Sinclair is assigned to protect the Federated Suns' control over the planet Vale and its resources against New Belt Pirates led by Susie Ryan.

[3] John Lee of NextGen called it "a worthy successor to the two earlier versions that should keep Mech pilots eagerly engaged until the mission packs start rolling out.

Alongside the underperformance of Starsiege and Heavy Gear II, the sales of the game led Asher to speculate that "the mecha market just isn't as big as we thought".

[29][30] In September 2000, Asher wrote that "the evidence seems to be piling up that games that require anything more than a keyboard and mouse for a control setup suffer at the cash register, [but] the FASA license is as strong as ever.

[32][33][34] The staff of CGSP wrote: "While it [MechWarrior 3] was light on quantity of missions, Zipper finally got the scale right in a Mech sim.