How Row Load Palindrome Mines Works

The board has four rows and four columns, with exactly four mines. The mine counts in the rows form a palindrome: row 1 has as many mines as row 4, and row 2 has as many as row 3. For example, row counts 1, 1, 1, 1 satisfy the rule, as do 0, 2, 2, 0. The positions within matching rows need not mirror one another. The game uniformly selects one of the 328 boards satisfying the four-mine rule at the start; it does not redraw the board after a reveal.

The current demo offers one mine configuration, Mines 4, and stakes of 10, 20, 50, 100, or 200 coins. Press Start round to debit the stake, then choose an eligible covered cell. Bank current quote becomes available only after at least one safe reveal. Stake, mine setting, and refill stay locked during the round; eligible cells, banking after a safe reveal, and sound remain available. There is no automatic queue of rounds.

After safe reveals, the gross quote is 0.96 × captured stake × 328 / N, where N is the number of initially legal boards compatible with every revealed safe cell. A mine returns zero. The compatible set can shrink or stay unchanged after a safe reveal, so the gross quote can increase or stay unchanged. The conditional chance that a covered cell is safe is the number of compatible boards where that cell is safe divided by N; it is not calculated from the unconstrained board alone.

Cells are labelled 1–16 in row order, from top left to bottom right. If Cell 1 is safe, 246 compatible boards remain and the gross multiplier is 0.96 × 328 / 246 = 1.28. If Cells 1, 2, and 3 are all safe, 100 boards remain and the multiplier is 3.1488. These are conditional quotes after successful reveals, not guaranteed paths. A 20-coin stake at 1.28 gives a gross quote of 25.6 coins before carry and rounding.

You may bank after a safe reveal. Revealing a mine ends the round with zero gross return. Revealing all twelve safe cells, or leaving no eligible reveal, automatically banks the current quote. Certain mines are disabled. The code also disables a reveal if its possible safe quote would exceed 1,000 times the stake; it does not clip a payout after the reveal. With this four-mine support, the greatest possible quote is 0.96 × 328 = 314.88 times the stake, so the 1,000-times guard is not reached.

For supported cell choices and banking policies, expected gross return is exactly 96% of the captured stake before whole-coin rounding. This includes returned stake, not 96% profit, and does not guarantee any individual round or session. A safe transition with probability Nnext / N pays a quote proportional to 1 / Nnext, where Nnext is the compatible-board count after that safe reveal; a mine pays zero. That relationship preserves the current expected gross value. Reloading an unfinished round is outside those settlement policies.

The mathematics checks compare the complete legal-board set against an independent enumeration of all 65,536 four-by-four bit boards. Six tested banking policies have exact gross return 96%. Five simulations use one million rounds each; the longest tested path uses fourteen million. Their measured returns range from approximately 95.911% to 96.147%. Those sample estimates support the exact expectation and do not determine a session outcome.

At settlement, gross return is added to the saved fractional carry. The whole-coin part is credited to the balance and the remainder below one coin is saved for the next settlement. Carry does not change the gross quote formula. A mine has zero gross return and preserves existing carry. The balance and carry use browser localStorage and can survive reloads, including a zero balance.

Reloading or closing the page during an unfinished round ends it without refund or resume. The stake was debited when the round started. Stored balance and carry can be read again while the site storage remains available. Clearing site data can erase both; clearing cached files alone may leave localStorage intact.