if an attack cost negative amount of energy you actually gain energy, I don't think that should be like that.
also, give some notification to which buffs and debuffs stuck and which doesn't
players should be able to see all the cards, perhaps even during game, because knowing the enemy character is so crucial.
also, in beta version, I think it would be best if we could change cards so we can experience different decks. if you choose unfitting cards before you got to play (so you don't really know how the game works) you're stuck with it
 "Dino Run")
 "Epsilon")
 "Spellblazer"){kind=icon}
 "Kongai")
 "colorfill")
 "Monsters' Den")
 "Campaign Game: General Election")
 "Orbox B"){kind=icon}
 "Starfighter: Disputed Galaxy")
 "Indestruct2Tank")