would be nice to have a treasure card box at my house to save the ones i craft with. Be used just like the seed vault.
This would be a good thing and it's been suggested many times in the past. In the meantime... you can take the decks you can't use... like the ones that are school specific... and instead of selling them, use them for TC storage. When you put a TC in a deck it no longer takes up space in your total card count so if you carry five un-usable decks with 20 TC spots each that gives you 100 TC over and above the 999 card cap limit. Rename them "Treasure Card" decks and they'll be easier to find. I do this for specific types of spells... a deck for shields, one for blades, one for buffs, one for polymorphs, one for minions etc.
You find treasure cards from your school tree. Get a treasure card crafting table in Krokotopia, the furniture guy right after you finish the boat ride.
