AERENA - Masters Edition was released on Steam with trading card support on 10 February 2015. There are 5 cards in the series, and you'll receive 3 cards at random for purchasing and playing the game.
This is an updated version of Aerena - Clash of Champions, moving the game from Free to Play to the standard 'purchase and own' model. Though the two games are fundamentally the same, they have separate card sets.