YJL

Blue Moon is a type of Patience game, it’s also called Gaps.

Click to watch a complete game played

This 52-card solitaire starts with the entire deck shuffled and dealt out in four rows. The aces are then moved to the left end of the layout, making 4 initial free spaces. You may move to a space only the card that matches the left neighbor in suit, and is one greater in rank. Kings are high, so no cards may be placed to their right (they create dead spaces).

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The rule sounds like a lot, but you only needs four keys to play with and it doesn’t take a lot of time to finish one game. It seems always solvable:

A moment’s reflection will show that this game cannot take more than 13 deals. A good score is 1-3 deals, 4-7 is average, 8 or more is poor.

The real skill in this game is just how many deals does it take.

Blue Moon was originally created by Tim A. Lister in C, Eric S. Raymond added ncurses on 1994-11-28 for visual user interface and color support, licensed under the Simplified BSD License (2-clause), currently git-4223982 (2015-10-17, post v2.12 (2014-05-30))