The selling of card in public or private is available only after a purchase of credits (as a mean to stop multi accounts abuse).
See Game Help on the left side. Buying cards from other players and everything else is available immediatly.
Urban Rivals | Free Online Manga Trading Card Game | TCG | MMO
The Urban Rivals team is made by lovers of all kind of Collectibles Cards Games and Trading Cards Games like: Magic the Gathering, Dominion, Vampire, Yu-Gi-Oh!, Pokemon, Wakfu TCG, Assassin Creed Recollection, Shadow Era, Kard Kombat and Might & Magic Duel of Champions.