Single Left

Game Objective:

The primary goal in Single Left Solitaire is to remove cards from play according to specific discard rules, ultimately leaving only a single card remaining in your hand or play area.

Setup & Layout:

• Use a standard 52-card deck with no Jokers.
• Hold the entire deck face down in one hand.
• The play area consists of the cards in your hand, with four cards fanned out on top so their suit and rank are visible at all times.
• There are no tableau, foundation, stock, waste, or reserve piles in this variant. All play occurs within the hand-held deck and the visible cards.
• Cards are always drawn face up when fanned, but the rest of the deck remains face down.

Single Left Solitaire Rules:

• Always maintain four cards visible at the top of the hand-held deck.
• After each action, if there are fewer than four cards visible, draw from the back (bottom) of the deck to restore four visible cards.
• Discarding:
• If the first and fourth visible cards share the same suit, discard the two middle cards (second and third).
• If the first and fourth visible cards share the same rank, discard all four visible cards.
• After discarding, rearrange the hand so that four cards are again visible at the top. If necessary, draw from the back to restore four visible cards.
• If neither discard condition is met, draw one card from the back and add it to the right end, then check again for discard conditions.

Gameplay:

• Begin by fanning out the top four cards from the hand-held deck.
• Check for discard conditions:
• If the first and fourth cards are the same suit, discard the two middle cards.
• If the first and fourth cards are the same rank, discard all four cards.
• After discarding, refill the visible cards to four by drawing from the back as needed.
• If no discard is possible, draw one card from the back and add it as the new fourth card, shifting the visible window one card to the right.
• Repeat this process—checking for discards, discarding, and replenishing visible cards—until the deck is exhausted or only one card remains.
• If at any point there are fewer than four cards left, display all remaining cards as the visible set and continue applying the rules.

Winning & Losing Conditions:

• Win: You win if you successfully discard all cards except for a single card, leaving only one card in your hand at the end of the process.
• Lose: The game is lost or unwinnable if you reach a state where no further discards are possible and more than one card remains in your hand.

Special Rules & Edge Cases:

• Refilling the visible cards: After any discard, always restore the visible set to four cards if possible by drawing from the back of the deck.
• Insufficient cards: If fewer than four cards remain, use all remaining cards as the visible set and continue checking for discard opportunities.
• No further moves: If you cannot make any legal discards and cannot draw more cards to create a set of four, the game ends.
• Optional Variation: Some versions allow for a redeal after the deck is exhausted, using the discarded cards in their original sequence to increase the odds of winning, but this is not standard.

Note: The rules above are based on the most authoritative description of "Single Left Solitaire" as a one-handed solitaire variant, sometimes also called "One-Handed Solitaire". If you are seeking a different variant, please specify, as the name may refer to other less common rule sets.