It is unknown when and where the trend began, but it has now become a staple for most TCGs and is usually something optional for members to participate in.
Each TCG handles them differently: some give you unlimited copies of your own card to trade and collect, while others make you earn them. Some TCGs even let members create a new card each time they reach an achievement in the game and eventually create a complete deck.
A few TCGs have added a "twist" by letting members create their own decks. While a normal member card is typically given to a member upon joining, decks are usually unlocked by completing tasks on the website.
- Example: Elements.