What is the name of Halo: Campaign Evolved's prequel campaign led by Master Chief and Sgt. Avery Johnson?

Halo: Campaign Evolved’s prequel campaign led by Master Chief and Sergeant Avery Johnson is called Operation: METEORITE. It is a three-mission story set before the events of Halo: Combat Evolved.

The operation takes place in 2551, one year before the original game. Master Chief and Johnson are sent behind enemy lines to infiltrate the Covenant research vessel Triumph of Tolerance, which is positioned above Promise, a human colony that has been glassed. Their mission connects military action with the wider mystery of Covenant technology and leadership.

Operation: METEORITE is more than a renamed version of a classic Combat Evolved level. It is new campaign material created for Campaign Evolved, giving Johnson a central role alongside the Chief and introducing additional enemies, weapons, and narrative context.

The title can be confused with other Halo operation names. Operation: FIRST STRIKE is associated with a later Halo novel and storyline, while Operation: TORPEDO belongs to earlier Spartan-II history. Neither is the name of Campaign Evolved’s new prequel campaign.