Locking Cards

[PirateKingAtomsk]

This would allow you to lock cards you don't want to sell.  When my Rainbow deck isn't active I have a ton of card slots up when I go to the Bazaar.  I usually end up worrying that I will sell a rare card, I have 3 of them that aren't in my rainbow but I don't want to sell them in case they become something I need later.  This would allow people to not accidentally sell cards.

[Kamietsu]

It warns you when you are about to sell a rare card. You then have to click on it again to actually sell it.

[tyranim]

its not a bad idea, but its not a good one either. not all that important imo