i'm still working on figuring out the rules fully but as far as i understood it, it's not just a normal deck right? it's pretty heavily altered it looks like?
It’s a modified deck (Ace-6 and faces from spades and clubs, Ace-9 and faces from hearts and diamonds, and one joker), but it doesn’t require any proprietary cards. You can make a new card stack in Foundry and exclude the cards you don’t need.