As the official release of Battlefield 1 draws nearer, here's everything players need to know about the collection of unlockable Codex cards that's included in the game.

Despite the fact that Battlefield 1 doesn't officially release until this Friday, many players have already had chance to access the game via its Early Enlister Edition or the free trial currently available on EA Access. Anyone that's already spent some time on the frontlines has likely earned a few Codex cards.

Codex cards are a new addition for Battlefield 1, and are intended to flesh out the painstakingly researched historical backdrop of the game. Players will see an on-screen pop-up whenever they unlock a new card and add it to their collection.

However, it's not possible to access this content in the game itself — at least for the time being. Players who want to review their collection of Codex cards should head to the official Battlefield website, and check out the Career section of the web companion.

This content is broadly similar to the Grimoire cards that were used to give the world of Destiny some much-needed backstory. That said, given that Bungie has been widely criticized for the fact that the Grimoire isn't accessible in-game, it's strange that DICE would make a similar decision with regards to the Codex cards of Battlefield 1.

Like the Grimoire cards in Destiny, Battlefield 1 players can earn Codex cards by completing a variety of in-game challenges. Here, these challenges typically relate to amassing a certain amount of kills with a particular weapon, winning multiplayer skirmishes on particular maps, and accomplishing specific campaign objectives, according to a report from VG247.

Completing these challenges will earn individual cards, that offer up information on various aspects of World War I. The cards are sectioned off into distinct categories; three that cover the weaponry, vehicles, and tactics utilized in the conflict, one that focuses on the war as a whole, and another that looks at the wider world at the time.

Given that Battlefield 1 marks a return to historical warfare for the franchise, this kind of educational element is a great addition to the game. There are bound to be many players that don't know a great deal about the real-world conflict of World War I, and the Codex cards seem poised to fill in some of those gaps.

Codex cards may be a relatively small part of the Battlefield 1 experience, but they're indicative of the approach DICE has taken with regards to the game as a whole. Despite the fact that most consumers will be attracted by jaw-dropping visuals and the promise of compelling multiplayer, there's some legitimate historical content on offer for anyone interested in learning more about World War I.

Battlefield 1 is set to launch on October 21, 2016 for PC, PlayStation 4, and Xbox One.

Source: VG 24/7