Warlock Pact: The Cards

Your patron gives you a deck of portentous playing cards, called a Deck of Fate, which you may use as an arcane focus. If your Deck of Fate is lost or destroyed, it reappears whole on your person after a long rest.

You gain proficiency with playing cards. Your proficiency bonus is doubled for any ability check you make that would use that proficiency.

You may replace one of your d20 rolls with a card from your Deck of Fate. Draw a card and use the value on it, with Aces, Jacks, Queens, and Kings all counting as a 20. You may use this feature after seeing the initial roll, but before knowing the outcome, and you must use the outcome indicated by the card. Afterwards, shuffle your Deck of Fate. You may not use this feature again until you finish a short or long rest.

To use this pact you will need a standard deck of 52 playing cards, not including jokers. Any attempt by the warlock to tamper with the deck or cheat in its use results in the deck instantly and permanently being destroyed by their Patron.