The run ends when the beach fills to the top. Merge tiles to keep space open — the longer you last, the higher the score.
Tap a ▼ lane to drop the falling tile — beat the clock, or it drops in a random lane.
Touching tiles with the same numeral merge into one bigger tile: I+I→II … IX+IX→X. Two X’s = 💥.
Every 12 drops the tide rises — a new stage: faster clock, richer tiles, level bonus.
🏆 Points: bigger merges pay more · same sport = ×2 · extra merges from one drop chain ⚡×2, ×3… · everything × your level.
Score 0Best 0Level 1⚡12
Drop before the clock does
Next
Tap a ▼ lane to drop.
SurfDoku
An OpenDoku game · Open Mirror LLC
The climb: green teaches the moves, yellow flag plays numeral AND sport at once, the red flag is a pure icon sudoku, and the double red flag is the summit — two full sudokus in every tile.
How to play — Low Tide
Every tile is two puzzles at once — the numeral and the sport both have to fit. Pick a card below, then tap where it goes.
Green flag: the kiddie pool — I, II, III and IV in four different suits. Every card fits anywhere; just learn to pick up and place. The rules kick in on yellow.
Yellow flag: 4×4 — every row, column and 2×2 box needs each numeral I–IV and each sport once.
Red flag: 9×9, icons only — every row, column and 3×3 box needs all nine beach games. Big clean tiles, one constraint, real sudoku depth.
Double red flag: the true summit — 9×9 where numerals I–IX AND nine sports are both sudoku-valid at once. Two puzzles in every tile.
The lineup is exactly the right cards to finish the board, and you never have to guess — guaranteed. From the first tile to the last, there is always a cell that accepts exactly one of your cards, or a card with only one home. Start where a row, column or box is fullest, and if you can’t see it, 💡 will.
A move that breaks the rules — or would make the beach impossible to finish — gets an ✗, but the card comes back to you to try somewhere else. Mistakes add up: three ✗ in one run and you’re out. Every deal is solvable.
💡 is your coach — it glows a correct card and spot when you’re stuck — and costs one ✗.
Your game saves itself — close the app, come back, keep climbing.
How to play — Riptide
The goal is survival: the run ends when the beach fills to the top. Merging keeps it clear — and scores.
Tap a ▼ lane (or anywhere in a column) to drop the tile there before the clock drops it for you in a random lane.
Touching tiles with equal numerals merge upward: I+I→II … IX+IX→X. Two X’s vanish in a 💥 worth 500 × level.
Scoring: bigger merges are worth more. Same-sport merges pay double. Every extra merge set off by one drop is a ⚡ chain — the 2nd merge pays ×2, the 3rd ×3. Everything is multiplied by your level.
Every 12 drops = next level, each a stage of the tide: 💧 Ripple → 🫧 Chop → 🌊 Swell → 🌀 Undertow → 🦈 Shark Water → 💥 Riptide → 🌌 Open Ocean. The clock gets faster (6 seconds down to 1.8), IV tiles roll in more often from level 4, V breakers from level 6, and every level pays a bonus. A red lane is one tile from the top — clear it first.