Violet can take corner R6C1 or play R1C5. Which move wins with correct continuation?
Make a prediction before opening the reasoning.
Compare the predictions
- R6C1: take the stable corner.
Not supported. Cream then plays R1C5 and wins 19–17.
- R1C5: force a pass, then take the corner.
Supported. Cream has no legal move; Violet plays both remaining squares and wins 20–16.
- Both moves draw.
Not supported. Both complete endings have unequal final disc counts.
Predictions stay on this page; they are not saved or sent.
Test this exact position
Try the alternatives, then undo or reset before comparing another branch. The written argument below always starts from the original position. Played moves save locally in this browser; predictions do not.
Loading playable study…
Select a legal empty square. Violet (V) and Cream (C) are the two players. You control both sides here. Bracketed discs flip automatically; a player without a move passes automatically.
Keyboard: Tab to an enabled control, then press Enter or Space. The study starts from the diagram shown; reload can restore your own saved moves.
Try the task before inspecting the answer.
The position and the question
Corners are stable: once occupied, that corner disc cannot be flipped. That is a true local fact. It does not establish that taking an available corner wins the whole game. With only two empty squares left, we can inspect both complete endings instead of relying on a heuristic.
The diagram is a reachable 6 × 6 position, reconstructed by the recorded legal opening history in the verification data. Automatic passes follow the same rules as the playable game. The winner is decided by the final number of discs.
Show the reasoning
Take the attractive corner first
Violet at R6C1 brackets the diagonal through R5C2 and R4C3, flipping two discs. The count becomes Violet 18, Cream 17. However, Cream now has a legal move at R1C5. The apparent lead is not the final score.
CR1C1CR1C2CR1C3VR1C4·R1C5CR1C6CR2C1CR2C2CR2C3CR2C4CR2C5CR2C6CR3C1CR3C2CR3C3VR3C4VR3C5VR3C6CR4C1CR4C2VR4C3VR4C4VR4C5VR4C6CR5C1VR5C2VR5C3VR5C4CR5C5VR5C6VR6C1VR6C2VR6C3VR6C4VR6C5VR6C6After Violet takes R6C1: Cream to move, Violet 18–17. Finish the corner-first branch
Cream at R1C5 flips the Violet disc at R1C4, bracketed by Cream at R1C3. The board is full. Cream finishes with 19 discs and Violet with 17. The corner itself stayed Violet throughout; its stability did not protect the rest of the score.
CR1C1CR1C2CR1C3CR1C4CR1C5CR1C6CR2C1CR2C2CR2C3CR2C4CR2C5CR2C6CR3C1CR3C2CR3C3VR3C4VR3C5VR3C6CR4C1CR4C2VR4C3VR4C4VR4C5VR4C6CR5C1VR5C2VR5C3VR5C4CR5C5VR5C6VR6C1VR6C2VR6C3VR6C4VR6C5VR6C6Corner-first ending: Cream wins 19–17. Play R1C5 first instead
Violet at R1C5 flips just R2C5, giving Violet 17 and Cream 18. Cream has no legal move at the sole empty square R6C1, so Cream must pass. Violet keeps the move and takes R6C1, flipping R5C2 and R4C3.
CR1C1CR1C2CR1C3VR1C4VR1C5CR1C6CR2C1CR2C2CR2C3CR2C4VR2C5CR2C6CR3C1CR3C2CR3C3VR3C4VR3C5VR3C6CR4C1CR4C2CR4C3VR4C4VR4C5VR4C6CR5C1CR5C2VR5C3VR5C4CR5C5VR5C6·R6C1VR6C2VR6C3VR6C4VR6C5VR6C6After Violet plays R1C5: Cream has passed, and Violet moves again. Count the completed alternative
After the forced pass and corner capture, the board is full with Violet 20 and Cream 16. The smaller initial capture wins because it changes who gets to play the remaining square. Both legal first moves and every continuation have now been exhausted; this is an exact ending, not a prediction from a mobility score.
CR1C1CR1C2CR1C3VR1C4VR1C5CR1C6CR2C1CR2C2CR2C3CR2C4VR2C5CR2C6CR3C1CR3C2CR3C3VR3C4VR3C5VR3C6CR4C1CR4C2VR4C3VR4C4VR4C5VR4C6CR5C1VR5C2VR5C3VR5C4CR5C5VR5C6VR6C1VR6C2VR6C3VR6C4VR6C5VR6C6Quiet-first ending: Violet wins 20–16.
The tempting shortcut
A stable corner and a one-disc lead make R6C1 the winning move.
Where the shortcut breaks
Cream’s final move overturns that temporary lead. Stability applies to the corner disc, not to the match result.
A better decision
When the ending is short enough, calculate to termination and include forced passes before comparing final disc totals.
Changed conditions
In a constructed variation, change R1C6 from Cream to Violet while keeping Violet to move. Do the same two move orders still give the same outcomes?
Check the changed-condition answer
The legal moves, captures and forced-pass pattern are unchanged. However, the starting disc balance changes by two: Violet gains one disc and Cream loses one. Corner R6C1 first, followed by Cream at R1C5, now ends 18–18: a draw. R1C5 first still forces Cream to pass; Violet then takes R6C1 and wins 21–15. The quiet move remains better, but the claim that corner-first loses no longer holds. This is a supplied counterfactual board, not a position attributed to the recorded opening history.
Take this back to your next game
Check the scope of a strategic rule. A stable corner is a local guarantee; the final score depends on the entire remaining sequence.
How the claim was checked
Replay 30 recorded legal moves from the 6 × 6 opening, then exhaust both two-square endings.
- R6C1 first: Cream wins 19–17
- R1C5 first: forced Cream pass, Violet wins 20–16
- All legal first moves: R1C5 and R6C1
- Constructed R1C6→Violet variation: corner-first draws 18–18; quiet-first wins 21–15
Read the fixed positions and supporting proof data. Computational checks establish only the claim and position stated here. They do not establish a player difficulty rating or make an unproved strategy optimal.
Playfield Arcade · Updated 4 October 2026 · Original case design, AI-assisted writing and code, with reproducible position checks. Our method · Report a correction