What is the hardest solitaire game?

Russian Solitaire is Yukon with one merciless change: tableau builds must follow suit instead of alternating colour. You can still move any face-up group, but the legal landing spots collapse, and under one deal in ten falls even to careful play. It's widely considered the toughest single-deck game worth playing.

Forty Thieves uses two decks, builds down in suit one card at a time, and gives you a single pass through the stock - no redeals. Every skipped card is gone for good, so a buried card at the wrong moment can be fatal. Napoleon supposedly played it in exile; the story fits a game this demanding.

Four-suit Spider asks for eight complete King-to-Ace runs, all in suit, and even strong players win well under 20% without undo. Scorpion adds genuine deadlock loops where two cards block each other. For the odds across every game, see our winnability guide.