Question 1

How do I play The Cube (3D Sudoku)?

Accepted Answer

The Cube is sudoku on the six faces of a 3D cube. Each row, column, and face must contain the numbers 1–N exactly once (N depends on the cube size — 3³, 4³, 5³, and so on). Rotate the cube by click-and-drag or arrow keys. Tap a cell, then tap a number to fill it in. The puzzle is solved when every row, column, and face is complete and consistent.

Question 2

How is The Classic different from regular sudoku?

Accepted Answer

The Classic is traditional 2D sudoku with one twist: you can choose your grid size (4×4, 9×9, 16×16, or 25×25). The 9×9 grid plays exactly like the sudoku you already know. Larger grids use the same rules but with more symbols per row, column, and box.

Question 3

What is The Avalanche?

Accepted Answer

Avalanche mode adds gravity: solved rows collapse and new rows drop in from above. You solve under continuous pressure as the cube state keeps shifting. Best for players who want a faster, more chaotic challenge.

Question 4

What is The Blitz?

Accepted Answer

Blitz is timed cube sudoku. You get a fixed interval (10 seconds by default — adjustable in settings) to place each number, or that section of the cube resets. Pure speed and pattern-recognition mode.

Question 5

What is Skyscraper?

Accepted Answer

Skyscraper is a 2D logic puzzle where numbers represent building heights. Clues around the grid tell you how many buildings are visible from that direction — a taller building hides shorter ones behind it. Place 1–N so every visibility clue matches.

Question 6

What does "Perfect" mean?

Accepted Answer

Perfect mode requires you to solve the puzzle without a single wrong placement. Make one mistake and the run is invalidated. Solves logged in Perfect mode are marked with a ✦ symbol on the leaderboard — harder to earn, but they show off your pure logic ability.

Question 7

How do Hints work?

Accepted Answer

A Hint reveals one correct cell. Using any hint marks the run as hint-assisted: it is not added to the global Hall of Fame and can't be a Perfect (❆) run. It still counts in your personal stats and personal best on this device. Hints are turned off in Daily Challenges.

Question 8

How do Notes work?

Accepted Answer

Notes (also called candidates or pencil marks) let you jot down possible numbers in a cell before committing. Tap the pencil icon, then tap a cell, then tap numbers — they appear small in the corner. Tap again to remove. Toggling pencil off returns to confirmed-entry mode.

Question 9

How do I challenge a friend?

Accepted Answer

After completing any puzzle, tap Share — Cubedoku copies a link containing the exact puzzle you just solved. Send it to a friend; they open it and play the same board. The link is short and contains no personal data — just the puzzle seed and your game settings.

Question 10

What qualifies for the global Hall of Fame?

Accepted Answer

A run reaches the global Hall of Fame only if it used no hints, has leaderboard upload enabled with a nickname, and passes the basic server checks. Hint-assisted runs stay in your personal stats on this device. Daily Challenges have their own separate board and are always hint-free.

Question 11

What do I get with Cubedoku Pro?

Accepted Answer

Cubedoku Pro is $1.99/month and includes: (1) ad-free across all modes, (2) Expert difficulty unlocked on every mode, (3) a Pro badge next to your nickname on the leaderboard (the leaderboard itself is free for every signed-in player), (4) early access to new modes. Cancel anytime. Billed by Paddle as merchant of record.

Question 12

Can I get a refund?

Accepted Answer

Yes — we offer a 14-day no-questions-asked refund on any Pro subscription. Email support@cubedoku.com with the email address you used at checkout, and we'll process the refund within 2 business days. Per Paddle's terms, refunds return to the original payment method.

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