Denpa Ningen no RPG Free! is a collectible card game released by Bandai in Japan in August 2015, produced as a tie-in to the free-to-play Nintendo 3DS title of the same name developed by Genius Sonority. The card game's primary distinguishing feature was its integration with the digital game: each physical card carried a unique code on its reverse that, when entered into the 3DS title, unlocked a corresponding Denpa Man character or piece of in-game equipment. Rare cards provided exclusive items otherwise unavailable in the game. The base card set contained 60 cards, distributed across three rarity tiers: 30 normal cards, 20 rare cards, and 10 High Rare cards. Booster packs of six random cards retailed for 200 yen, while three-card packs were also sold through Carddass vending machines for 100 yen. A second booster pack was subsequently released. All card codes have since expired, severing the link between the physical cards and the game, but the cards remain collectible objects among Denpa Men franchise enthusiasts.
Source: www.perfectly-nintendo.com/denpa-ningen-no-rpg-free-getting-a-trading-card-game-in-japan/