TwigRTS posted a topic in SuggestionsTitle says it all. Whether the idea is a long-shot or not, I just figured it would be cool to implement for convenience purposes.
For example, what card did you enjoy using in PvE/PvP simply because of what it could do in-game? Although I never played that much Shadow, I really enjoyed using Knight of Chaos with the "Tainted Chaos" ability. If you ever had to deal with large, clumped up armies, you could just summon this nonsense, waltz him right into the center of said army (carefully avoiding a quick death), and cause everyone around him to get into a mad fist-fight and come out with some free damage dealt.