Cascade Solitaire

Most solitaire games deal you unwinnable shuffles about one time in five and never tell you. Cascade runs a solver over every deal before serving it — if there's no path to a win, you never see that deal. A loss here is always your move, never the shuffle.

The solver does something better than filtering, though. Mid-game, you can ask "can I still win this?" If the answer is no, it searches back through your own move history and finds the exact move where the last winning line disappeared — "this deal became unwinnable at move 23" — and offers to rewind you to just before it. It changes how you learn the game. (Our data across 608 lost games: the median game is already dead at move 31, and the player goes on to make another 115 moves that can't matter.)

Three games, one shared daily:

• Klondike — Draw 1 or Draw 3, both verified winnable
• Spider — one, two, or four suits
• FreeCell — standard Microsoft deal numbers, so #617 here is the same #617 everywhere

Every midnight, the whole world gets the same Daily Deal. Solve it, keep your streak, compare times with friends on the exact same cards. There's also a three-deal Daily Gauntlet if one isn't enough.

Free. No account, no download, no ads over the game. Works well on phones. Progress saves in your browser.