Miss Milligan meets two-deck Klondike: alternating-color builds, growing tableau piles, and a friendly 75% chance of winning.

Milligan Harp Solitaire mixes Miss Milligan with Harp Solitaire, the two-deck Klondike variant. Expect to win about 75% of the time here, which lands it at medium difficulty. It's played with two decks, and both skill and luck matter here.
Miss Milligan Solitaire and Milligan Yukon Solitaire are the closest relatives, same family with different twists.
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.
8 tableau piles: Alternate color build down. Sequences of alternating colors move together as a group. Any card, or valid group of cards, can fill an empty pile. At the start of the game, the first pile gets one card, the second gets two, and so on up to eight. Only the top card of each pile is dealt face-up.
Stock: Click to deal one card to every tableau pile at once. There are no redeals.
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 diamonds is the K of diamonds. There can be no more than 13 cards in a pile.
The top card of each foundation can be moved back into play if another pile will accept it.
Eight tableau piles, growing from one card in the first pile up to eight in the last. Only the top card of 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 cards that fit on a 10 of clubs are the 9 of hearts or 9 of diamonds.
Cards on the tableau that are not covered by another card are free to be played onto the foundation or any other tableau pile.
Any card, or a valid group of cards, can fill an empty tableau spot.
Sequences running high to low in alternating colors can be moved together as a group.
The stock is made up of leftover cards.
When you click on the stock, one card is dealt to the top of every tableau pile at once.