11 Diamond is a free Queens-style star battle logic puzzle: place one diamond in every row, every column and every color region of the grid — with no two diamonds touching, not even diagonally. Every puzzle has exactly one solution, and it can always be reached by logic alone, with no guessing required.
Tap any cell to cycle through three states: empty → ✕ mark → 💎 diamond. Use the ✕ marks to note cells that cannot hold a diamond, then place diamonds where the rules force them. The board gives instant feedback as you eliminate impossible cells, and the difficulty label updates with each level.
Play the daily challenge for contest points, train in endless mode, and read the strategy guide for advanced techniques like region overlap, row elimination and the two-cell rule.
Yes. The game is free to play, with free daily challenges, endless mode and a monthly contest. No account or payment is required to play.
Place one diamond in each row, each column and each color region. No two diamonds may touch, not even diagonally. Each puzzle has one unique solution reachable by logic.
A new daily challenge is published every day at 00:00 UTC, and past puzzles stay available in the daily archive with their solutions.
Solve daily and endless puzzles to earn points each month. The top player wins a real 2-carat lab-grown diamond ring, sponsored by BVDIY. Full rules are in the contest terms.
Yes — contest scores are tied to an account so the leaderboard can be verified. Sign up from the contest panel, then sign in each time you play.
No. Every 11 Diamond puzzle is designed so the solution can be deduced with logic alone. If you feel stuck, the hint button and strategy guide will point to the next logical step.
Pure logic — not a single guess.
You collected all 11 carats.
In the full release they can be redeemed for a real lab-grown diamond.