War for Cybertron is played from a third person perspective. Transformers are classified into four main categories, Leader, Soldier, Scientist, and Scout. Each character in the campaign is classified as one of these types, and their weaponry, abilities and vehicle form are largely influenced by their character class. Players can change between forms at will, and each form has unique abilities. While in robot form characters can also collect different weapons, reminiscent of those found in first-person shooters. While in vehicle form each character can boost their speed.
Each campaign level gives the player a choice of three Transformers. The campaign can be played in single-player or cooperatively via online multiplayer, and players can enter or leave the game at any time. If fewer than three players are present, the game's AI controls the remaining playable characters. Cooperative and competitive modes of the game are limited to online play, with no split screen features available. The game levels are designed to allow characters to comfortably navigate and play the game in either mode.
In the Decepticon campaign Megatron fights to return the Transformers' home planet of Cybertron to what he refers to as a golden age. It opens as Megatron, having heard legends about Dark Energon, an unstable substance with the power to corrupt life on the planet, and the Decepticons attack an orbital research station guarded by Starscream and his forces. Megatron, Barricade and Brawl reach the Dark Energon manufacturing plant, and Megatron immerses himself in it. Inspired by Megatron's ability to handle the Dark Energon, Starscream asks him to teach him how to control it in return for his service. Shocked by his betrayal, Starscream's colleague Jetfire escapes the space station, vowing to warn the Autobot leader Zeta Prime.
Megatron sends Starscream, Thundercracker, and Skywarp to reactivate an Energon bridge which will feed the station with raw Energon, allowing the manufacturing of more Dark Energon. Once they succeed, Megatron then develops a plan to infect the core of Cybertron with Dark Energon, feeling that he can gain control of the planet once it is infected. He launches a full-scale assault on the Autobot capital city of Iacon, looking for an item called the Omega Key, which he will use to enter Cybertron's core and infect it. The Decepticons learn that Zeta Prime has placed the key under his personal guard. Megatron's forces enter the chambers of Zeta Prime and defeat him in battle, taking him prisoner. Zeta Prime tells Megatron that the Omega Key is not actually what unlocks access to the core, but is the means to activate the true key, a colossal Transformer known as Omega Supreme.
Now activated, Omega Supreme pursues Megatron and his minions relentlessly. Megatron, Soundwave and Breakdown devise a plan to lure Omega Supreme to a rooftop defended with turrets, where the giant Transformer is ambushed. Omega Supreme sustains heavy damage and plummets to Cybertron's lower levels. The Decepticons follow Omega Supreme and engage him in a lengthy final battle, in which Omega Supreme is finally defeated, infected with Dark Energon, and captured by the Decepticons. Megatron forces Omega Supreme to open the door to Cybertron's core and travels there with his minions. Upon arrival he infects the core of Cybertron, also a Transformer, with Dark Energon, which then begins to spread over the entire planet.
In the Autobot campaign Zeta Prime, leader of the Autobots, is reported dead and Bumblebee informs Optimus of this. Optimus then decides to temporarily take the mantle of leadership. Optimus, Bumblebee, and Ratchet lead a defensive campaign to protect their home city of Iacon. The trio activate the city's defense guns and reactivate the communication grid. They then travel to the Decagon where the three Autobots battle Starscream and force him to retreat.
Shortly afterward, the Autobots receive a distress call from Zeta Prime, who informs them that he is being held at Kaon prison. Taking Bumblebee and Sideswipe with him, Optimus allows himself and the others to be captured in order to infiltrate Kaon. With help from Air Raid, the Autobots succeed in releasing all of Kaon's Autobot prisoners, who escape on Decepticon transports. Optimus, accompanied by Bumblebee and Sideswipe, find Zeta Prime's cell guarded by Soundwave. A fight ensues in which Soundwave deploys his minions Frenzy, Rumble and Laserbeak. Eventually, Soundwave and his minions retreat and the Autobots rescue Zeta Prime, who dies shortly thereafter from his previous injuries after his battle with Megatron. Optimus returns to Iacon with Zeta Prime's body and speaks with the high council who declares Optimus the new Prime and informs him of Megatron's activities.
Optimus is given the task of removing the Dark Energon from Cybertron's core by the council. Optimus, Ironhide, and Warpath first attempt to rescue Omega Supreme from the Decepticons, who is being tortured by Dark Energon. The Autobots free Omega Supreme and gain access to Cybertron's core. Struggling against a mysterious corrupted worm, Optimus then speaks with Cybertron's core, which informs him that it has been heavily damaged by the Dark Energon. It states that it can repair itself by shutting down, but the process will take millions of years during which Cybertron will become cold, barren, and lifeless. The core then tells Optimus that if he carries a small piece of the core with him, the core can still survive during the repairs. Optimus accepts the burden and the core relinquishes the Autobot Matrix of Leadership.
With the planet soon to shut down, Optimus orders the evacuation of all Autobot cities. As the Autobot evacuation transports reach orbit, many are attacked by Megatron's orbital space station. Silverbolt, Air Raid and Jetfire enter the station and destroy vital systems, and during the attack they realize that the station is actually a massive Decepticon known as Trypticon. The damaged Trypticon plunges into Cybertron, and the Autobots band together to narrowly defeat him in one final battle. In the aftermath of the battle Optimus commissions a massive vessel known as the Ark to transport the remaining Autobots into space. Optimus and a small band of remaining Autobots stay to defend Cybertron from Megatron for as long as possible.
- Air Raid
- Omega Supreme
- Optimus Prime
- Zeta Prime