|~ Zero to Agent Raymond.|
|“||This is my power. My will! I will never be anyone's puppet! Not again! I will destroy everything!||„|
|~ Zero as he loses control of the Ultimate Power.|
Zero, also referred to as Agent Zero, is the titular main antagonist of Red vs. Blue: Zero. He is the leader of Viper and seeks the Ultimate Power.
Zero, originally Agent One, was a GLASS operative who was friends with Axel, a fellow teammate under the Alliance of Defense. Zero's purpose was meant to be the leader of the newly formed Shatter Squad. However, the Great War had ended, making the need for Shatter Squad useless and the project was cancelled. Angered and betrayed over this, as well as the brutal experimentation conducted by Starlight Laboratories (AOD's science branch), Zero abandoned AOD. He later recruited Agent West's daughter Phase, who had been the subject of Starlight Laboratories' experiments that saved her life but also gave her powers, as well as powerhouse Diesel, forming the criminal syndicate Viper.
Seeking the Ultimate Power for his own purposes, Zero leads Viper in an attack on a facility containing an alien artifact. They battle the soldiers there, as well as Freelancers Carolina and Washington, wounding the latter and stealing the artifact. Zero then has Phase tag along with him to one of the ancient temples where another artifact is located. The two of them defeat the temple guardian and claim the artifact as their own.
Zero battles Shatter Squad later and easily defeats them, taunting them, particularly their leader Agent One, for being shadows of his former self and minuscule in comparison to his powers. Phase steals Tucker's sword and returns to Zero, who prepares to launch an attack on the temple where the Ultimate Power is located. However, Phase and Diesel both learn that Zero actually has no idea what the Ultimate Power actually is and is blindly seeking out power without grasping its consequences.
Phase and Diesel hold off Carolina and the Freelancers as Zero finds the Ultimate Power, being a golden helmet that grants him a powerful armor. The alien construct guarding it, Black Lotus, watches him wield the armor as he battles Shatter Squad. Although Zero is easily taking them on, Black Lotus remains unimpressed with Zero, who fights off Black Lotus's presence and starts losing control of his power. With his loss of control and Phase's defection back to Shatter Squad, Zero is defeated. As he fails to comprehend how he could have lost even with the Ultimate Power, Black Lotus fuses with the armor and transports Zero away, leaving his fate unknown.
- Both Zero and Agent One, the main antagonist and main protagonist respectively, are confirmed to be African-American characters.