The indexes were subsequently replaced by a new series of codices. 'Codex' is now a term solely used for army books.Īt the launch of 8th edition all previous codices were replaced with index books due to a major rules overhaul (as of November 2019 these indexes are no longer produced). Games Workshop no longer produce campaign or battle zone codices, instead releasing 'expansions'. Until superseded by newer versions, the 3rd edition and later codices remained valid for the newer editions of Warhammer 40,000. The third edition rendered these obsolete, and a new series began, including introducing codices for battle zones and campaigns. Example 8th edition Codex (Space Marines) All codices have a standard grey title and border.Ī codex (pluralized as codexes by Games Workshop), in the Warhammer 40,000 tabletop wargame, is a rules supplement containing information concerning a particular army, environment, or worldwide campaign.Ĭodices for particular armies were introduced for the second edition of the game.