This Canfield twist drops the suit rule on the tableau, so any card follows any other by rank alone. That single-deck freedom lifts your odds to 20%.

Rainbow Solitaire is a Canfield Solitaire variant that drops Canfield's suit requirement entirely: on the tableau, any card can follow any other, regardless of color, as long as the rank is right. That one change makes the game noticeably more forgiving than standard Canfield. It's sometimes called "Rainbow Canfield" to keep it separate from Rainbow Fan, a different game entirely. Played with a single deck, it has a 20% win rate, with skill and luck sharing the credit.
Canfield Solitaire and Kansas Solitaire are its closest relatives; Chameleon and Storehouse use a similar free-suit idea if you want to keep exploring the family.
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4 foundation piles: Each pile starts on the same random rank and builds up in suit, wrapping from King back to Ace as needed, until it holds thirteen cards.
4 tableau piles: Build down, any suit. Sequenced runs move together, also regardless of suit. Empty spaces refill from the reserve; once the reserve is empty, any card can fill the gap. Each pile is dealt one card face-up at the start.
Stock: Click to deal one card at a time to the waste. There are no redeals.
Waste: The top card can be played to the foundations or tableau.
Reserve: Thirteen cards are dealt here at the start, with only the top card face-up. Its top card is available for play to the foundations or tableau.
There are four foundation piles.
Each pile starts on the same random rank, whatever card is dealt to it first. A card can be added if it is one higher than the pile's current top card and of the same suit, so the only card that can follow a 6 of diamonds is a 7 of diamonds. When a pile reaches King, it wraps to Ace and keeps going until it holds all thirteen cards of its suit.
The top card of any foundation pile can be moved back into play if another pile will accept it.
There is one reserve pile of thirteen cards. Only the top card is dealt face-up; the rest are face-down. No cards can be moved into the reserve. Its top card can be played to the tableau or a foundation.
Four tableau piles, each dealt one card face-up.
A card can be added to a tableau pile if it is one lower than the pile's current top card, regardless of suit. So a Jack will accept any 10.
Any tableau card not covered by another card is free to move to the foundation or another tableau pile.
Empty tableau spaces refill instantly from the reserve. Once the reserve is empty, any card can fill an empty space.
A run of cards in sequence, high to low, can move together from one pile to another, regardless of suit.
The cards left after the deal make up the stock, and there is one waste pile.
When you click the stock, one card deals to the waste. You only get one pass through the stock, with no redeals.
The top card of the waste can be played to the tableau or a foundation.