No mainline CoD game uses the single word "Codex" as a menu button—it’s a fan shorthand or secondary title (e.g., the WWII companion guide).

The primary objective of Operation Codex is to gather intelligence, conduct sabotage, and create chaos behind enemy lines, ultimately weakening the enemy's grip on Western Europe.

Call of Duty is a franchise defined by its massive scale, fast-paced gunplay, and blockbuster cinematic campaigns. However, beneath the surface of the multiplayer lobbies and Warzone drops lies a complex web of lore, mechanics, and history. To truly master the game, players often look for a definitive Call of Duty Codex—a central repository of knowledge that bridges the gap between casual play and tactical mastery.