Source: The Book of Many Things

Wondrous Item, uncommon

This deck of cards is decorated with geometric shapes that have a protective motif. While you’re holding the deck, you can use an action to shuffle it and cause the cards to deal themselves out and transform into a shelter made of cards. The shelter can be shaped however you desire, but it must fit in a 40-foot cube centered on a point within 30 feet of you. The shelter has one door and up to four windows, and only you can open or close them. It has a floor and a roof, and it maintains a comfortable temperature inside.

The shelter has AC 15, 50 hit points, and immunity to poison and psychic damage. The shelter lasts for 24 hours, until you dismiss it as an action, or until it is reduced to 0 hit points. When the shelter’s duration ends, it transforms back into a deck of cards and appears in your hand. Once the deck has transformed into a shelter, it can’t be used again until the next dawn.