. . "The collectible Enigma Code fragments appear in the game world as red booklets with a black Wolfenstein logo on the cover, followed by the words \"GEHEIM - Enigma Codes\". Most code fragments are scattered about in the open just up for grabs, though others are located well out of sight, usually requiring the player to traverse a hidden, sometimes dangerous area to reach. Interacting with certain objects in the environment in a correct manner will sometimes yield cleverly-hidden code pieces. Solving each code unlocks a bonus game mode with rules altered from the normal gameplay such as unlimited ammo, HUD removal, absence of collectibles and the inability to use or acquire perks."@en . . "Enigma Code"@en . "The collectible Enigma Code fragments appear in the game world as red booklets with a black Wolfenstein logo on the cover, followed by the words \"GEHEIM - Enigma Codes\". Most code fragments are scattered about in the open just up for grabs, though others are located well out of sight, usually requiring the player to traverse a hidden, sometimes dangerous area to reach. Interacting with certain objects in the environment in a correct manner will sometimes yield cleverly-hidden code pieces."@en . . . . . .