The functionality of card packs, as originally implemented, was a parody of the controversy surrounding the monetisation of free-to-play gaming: in particular, the mobile phone version of Dungeon Keeper and Star Wars Battlefront II. The minigame was developed as a parody of a number of similar trading card games, including Magic: The Gathering, Pokémon and Pokémon GO. Max Barry introduced Trading Cards on 1 April 2018, originally as the theme for the annual NationStates April Fools' Day minigame in 2018. The objective is to earn card packs by answering issues and build up a collection of trading cards of nations or trade them with other players. NationStates Trading Cards (or simply Trading Cards) is a virtual trading card game in NationStates.