A fully mechanical solitaire — no decisions required. Cards are dealt into 13 piles arranged like a clock face. Flip cards one at a time and see if all 48 non-King cards are revealed before the 4th King appears.
Solitaire.City includes classic builders, pairing games, and larger two-deck patience variants, so you can jump between quick rounds and longer strategic layouts.
Clock Solitaire is a fully mechanical patience game — there are no choices to make. The outcome is determined completely by the initial shuffle. Every move is forced by the rules, and the game either reaches a winning state or locks up, with the player unable to influence which happens. Like Perpetual Motion, Clock is a mathematical process whose result is revealed by running it to completion.
Despite (or because of) this, Clock has been a popular game for over a century, played by people who enjoy watching a shuffle play out as a self-contained mechanical puzzle. Win probability is approximately 1 in 13 — a King must not end up on top of the King pile until every other pile’s top card has been revealed.
Full rules
The 52-card deck is dealt face-down into 13 piles of 4 cards each, arranged in a clock- face pattern: twelve piles at the clock positions 1 through 12, and one pile at the center representing the King position. The top card of the center pile is turned face-up.
Place the revealed card face-up under the pile corresponding to its rank (Ace=1, 2=2 … Queen=12, King=center). Turn over the new top card of that pile. Continue: each revealed card goes to its rank position, and the top card of that pile is revealed next. Win if all 48 non-King cards are revealed before the fourth King is placed. Lose when the fourth King is placed and at least one pile still has face-down cards.
Why the outcome is fully determined by the shuffle
Every move in Clock is forced — the revealed card always goes to its rank pile, and the top of that pile is always revealed next. There are no choices. The game is essentially a traversal of a linked structure created by the initial shuffle.
The winning condition is equivalent to: in the initial shuffle, no King is in the 48th, 49th, 50th, or 51st position of the sequence generated by following rank-pile links. The exact probability of this is 1/13 (approximately 7.7%) regardless of any player decisions, because there are none to make.
Both Clock and Perpetual Motion are fully mechanical — no player choices, outcome determined by deal. Clock has a binary outcome (win or lose) decided in a single pass. Perpetual Motion may run indefinitely, cycling through deal-and-discard rounds until either all quartets are removed (win) or a loop is detected (draw/loss). Clock is faster and simpler; Perpetual Motion can run for many more rounds.
Related mechanical games
Perpetual Motion — four-pile forced deal; win or loop; longer run than Clock
Calculation — arithmetic foundations; has genuine player choices unlike Clock
Golf Solitaire — rank-based; simple rules but meaningful player decisions