Ten columns, just one pass through the stock, two full decks, and a tough 15% win rate: Moving Left tests real solitaire skill.

Moving Left Solitaire plays like Double Klondike Solitaire or Gargantua, but spreads the tableau across ten columns instead of nine and gives you only one pass through the stock. Tarbart described a similar layout as "Triangle" in a book from 1905; Thomas Warfield reworked it into the version you see here. It's difficult, with a 15% win rate over two decks. Skill helps, but so does the shuffle.
The same idea comes in other sizes: Single Left Solitaire uses one deck, and Triple Left Solitaire uses three. In all three, only a King, or a valid King-led run, can drop into an empty column. Nothing fills it for you automatically, despite the name.
If you run into anything odd or have an idea that would make the game better, please contact me.
Enjoy yourself!
8 foundation piles: Build up from Ace to King in the same suit.
10 tableau piles: Build down by alternating color, and move alternating-color sequences as a group. Empty columns can only be filled by a King, or a valid King-led run; nothing shifts in on its own. The deal is triangular: one card in the first pile, two in the second, and so on up to ten in the tenth, with only the top card of each pile dealt face-up.
Stock: Click to turn over one card at a time to the waste pile. There are no redeals.
Waste: The top card can be played on the foundations or tableau.
There are eight foundation piles.
A card can be added to a foundation pile only if it's one rank higher and the same suit as the pile's current top card, so the only card that fits on a Q of spades is a K of spades. A pile holds at most 13 cards.
The top card of each foundation can move back into play if another pile will accept it.
Ten tableau piles, with one card in the first, two in the second, three in the third, and so on. The top card in each pile is dealt face-up; the rest are face-down.
A card can be added to a tableau pile only if it's one rank lower and the opposite color of the pile's current top card, so the only cards that fit on the 9 of clubs are the 8 of hearts and 8 of diamonds.
Any uncovered tableau card is free to move to the foundation or another tableau pile.
Empty tableau spots can only be filled by a King, or by a valid King-led run of alternating colors. Nothing refills them for you.
An alternating-color sequence, high to low, can move from one tableau pile to another as a group.
There's one waste pile; everything left over makes up the stock.
Click the stock to deal one card to the waste. You only get one pass through the stock.
The top card of the waste can be played to the tableau or foundation.