Unreal Tournament 2004 was a supported title that has since been removed from the Steam Store.
Unreal Tournament 2004: Editor's Choice Edition had Steam trading card support added on 15 July 2013. There are 6 cards in the series, and you'll receive 3 cards at random for purchasing and playing the game.
As of 14 December 2022[1], the game has been delisted from the Steam Store. As such, its trading cards and crafting rewards can no longer be bought or sold on the Steam Community Market. The ability to trade them remains.
Trading Cards
Foil Cards
Badges
Booster Pack
Emoticons
Profile Backgrounds