In Doom: The Dark Ages, Codex Entries are collectible items that provide lore and background information about the game's world, characters, enemies, weapons, and story. They are typically found in Secret Areas or hidden locations within levels, rewarding exploration.
There are 26 Codex Entries in total, and finding them all will unlock the "Lore Nerd" Achievement / Trophy.
Doom SlayerVillage of Khalim Collectible. You can find this Codex entry at the top of the cliff.
Village of KhalimVillage of Khalim Collectible. You can find this Codex entry inside the Secret Area camp.
HebethHebeth Collectible. It's on the lowest level, in an area hidden behind some large crates.
Sentinel BarracksSentinel Barracks Collectible.
Deag LoricThe Holy City of Aratum Collectible.
The Holy City of AratumThe Holy City of Aratum Collectible. In the Secret Area (The Holy City of Aratum #6).
Kreed MaykrSiege - Part 1 Collectible.
Siege - Part 1Siege - Part 1 Collectible.
Siege - Part 2Siege - Part 2 Collectible.
Abyssal ForestAbyssal Forest Collectible.
Ancestral ForgeAncestral Forge Collectible.
King NovikAncestral Forge Collectible.
Prince AhzrakThe Forsaken Plains Collectible.
The Forsaken PlainsThe Forsaken Plains Collectible.
Sentinel Command StationSentinel Command Station Collectible.
SerratSpire of Nerathul Collectible.
Spire of NerathulSpire of Nerathul Collectible.
City of Ry'uulCity of Ry'uul Collectible.
The WitchThe Kar'Thul Marshes Collectible.
Temple of LomarithTemple of Lomarith Collectible.
Commander ThiraBelly of the Beast Collectible.
Harbor of SoulsHarbor of Souls Collectible.
Hell PriestsHarbor of Souls Collectible.
Commander ValenResurrection Collectible.
ResurrectionResurrection Collectible.
MarokReckoning Collectible.
