Wrestling Codex entries were added on 6/11/2015 and feature a large amount of wrestling history from the promotions featured within the game. They have no value other than a collectible or aesthetic value when set as an avatar. They may also unlock achievements within the game.
Codex entries are gained by 3 methods within the game.
Buy A Codex Entry : (-1000 LP) OR (-1000 PP)
Gain 1 Codex Entry for Winning ANY match in a Pay-Per-View
Gain 1 Codex Entry per 40 Bonus Points purchased
If you ever gain a codex entry you already own - you will instead receive purchase points and learning points equal to the rarity level of that codex*100 so a common is worth 100, uncommon 200, so on and so on.