Locking decks

I’ve been looking around the wiki and the forums, but nowhere can I find how to keep people from manually dragging cards into decks. I’d like to be able to restrict decks to the cards that are currently in them, so that players cannot accidentally drop a card or game piece into a deck it does not belong in.

Any ideas? I might have to do something with Trigger Commands I’m thinking–something that checks to see what deck a card is placed into and returning it to the proper deck if it is the wrong one.

If the decks don’t need to be directly accessible, you can keep them on a hidden map and then use buttons/triggers to draw/return cards. I normally handle mine that way.