User blog comment:GrimFuture7/How to Improve Transformers Legends, by DeNA (pt. 2)/@comment-65.96.212.168-20130612184126/@comment-10546820-20130612192607

That's a popular idea. But I doubt the devs will allow that because too much fraud can happen. For example, I can create a 2nd account on my 2nd device, and make trades in such a way to make one account have the best cards.