Two-deck variant
A challenging two-deck patience game. Two central reserve columns form the “Backbone” flanked by eight Rib tableau piles. A single “Coccyx” card sits at the base of the Backbone and must be played first before the Backbone cards become available. Build all 104 cards onto eight foundations in suit from Ace to King to win.
Play the Coccyx card first, then use Backbone and Rib cards to build the foundations.
Solitaire.City includes classic builders, pairing games, and larger two-deck patience variants, so you can jump between quick rounds and longer strategic layouts.
Backbone Solitaire is a two-deck patience game with an anatomically themed layout: a central Backbone column of face-down reserve cards, flanked by Rib tableau piles on each side. The Backbone cannot be accessed until a specific “Coccyx” card — buried at the bottom — is freed first. This gate mechanic creates a two-phase game: an opening phase focused on freeing the Coccyx, and a main phase managing the now- accessible Backbone reserve alongside the Rib tableau piles.
Two 52-card decks (104 cards). The Backbone is a central column of face-down cards; the Coccyx card at the bottom must be freed before any Backbone card is accessible. Rib tableau piles on each side build downward by suit. Eight foundations build upward by suit from Ace to King. A stock deals to waste; the waste top is always available.
Freeing the Coccyx requires clearing the rib cards that block it. Once the Coccyx is played to a foundation or tableau, the Backbone cards become accessible one by one.
The entire opening strategy of Backbone revolves around the Coccyx. Until it is freed, the Backbone reserve — which holds many critical cards — is completely inaccessible. Identifying the Coccyx card’s location and tracing the path to free it is the first planning task. Moves that do not advance the Coccyx liberation are neutral at best in the opening phase.
Once the Backbone opens, the game transforms into a multi-source management puzzle: Backbone cards become available as they surface, Rib tableau piles continue building, and the stock/waste pair provides additional card access.
Rib tableau piles build downward by the same suit — the same restriction as Napoleon at St Helena and Australian Patience. This limits each card to at most one valid tableau destination per rank (one copy of the next-higher same-suit card). Planning Rib moves requires tracking which same-suit card of one rank higher is accessible, and whether placing there helps or hurts the Coccyx liberation path.