Forty Thieves Solitaire

Two full decks instead of one go into Forty Thieves, dealt out into ten columns, with the familiar solitaire goal of building each suit up in order into the foundations above. There's no clock pushing you along, so a stalled game just sits there until you find the next move or decide to give up on it. Easy and hard modes control how forgiving the deal and the available moves are, which matters more here than in single-deck solitaire, since Forty Thieves has a reputation as one of the harder classic variants to actually win. It's a good one to keep open in a spare tab rather than something you sit down expecting to finish quickly.