Random cards being in Shandalar deck?

[sylviapsichosis]

As I've played, I've noticed random cards that I own (that aren't in my actual deck) are seemingly sometimes in my deck? I cannot find a rhyme or reason for this, my deck is 60 cards. It is quite annoying, as I cannot even play them due to being outside my deck's colors. Is there something that causes this? Thanks.

[Korath]

It's caused by liberating cities taken over by one of the wizards. The ante card you get for winning the duel - which is easy to forget about, since it's only shown before the duel; you get the "[Cityname] is freed! The people rejoice." screen instead of the normal "Won these cards" screen at the end - gets put into your current deck instead of just your collection. IIRC, it gets removed the next time you look at the deckbuilder.

[sylviapsichosis]

That's interesting. Thank you so much! This had me completely baffled for a long time.