Steam Trading Cards are randomly dropped out-of-game items for the PC/Mac Steam version of the game. The collection is made up of eight trading cards and their foil versions. The trading cards can be obtained by simply playing the game. Four cards will drop at random while playing. After the four initial cards drop, you must either gain randomly received booster sets that can only be received by people who are active on Steam at least once a week to continue gaining cards, trade for more, or buy them off of the Steam Community Marketplace. Cards you currently own can be clicked on in your Steam Inventory to reveal a full-sized version of the image, at a resolution convenient for wallpapers.
After completing a set of cards, the option to craft a badge commemorating the feat will become available. Alongside the badge, you will receive experience points to boost your Steam Account Level, an emoticon that can be used in chat or in discussions, a random profile background image themed around ESO that you can use on your Steam community profile, and a chance at receiving a coupon for a different game or DLC. There are five badge levels with increasing amounts of rewarded experience, requiring up to five complete sets. There is also a sixth badge for collecting a full set of foil cards.
Steam cards cannot be obtained in-game by those who purchase the game from the official website or from another distributor such as the Epic Games Store.