✖️ X-Sudoku
X-Sudoku (Diagonal Sudoku) adds two extra constraints to the Classic puzzle.
Rules
- All standard Classic rules apply.
- The two main diagonals (the highlighted “X”) must also each contain the digits 1–9 exactly once.
Strategy
The diagonals are extra constraints you can exploit — a cell on a diagonal belongs to its row, its column, its box AND the diagonal, so it’s often the most constrained place on the board. Start there.
🏆 Difficulties & scoring
This type can be played on all five difficulties. The score multiplier for X-Sudoku is ×1.2 — so every point counts for more on this variant. The "normal time" below is tuned for this type.
| Difficulty | Base score | Max (×1.2) | Normal time | Hints |
|---|---|---|---|---|
| easy | 150 | 360 | 6 min | 5 |
| medium | 300 | 720 | 11 min | 4 |
| hard | 600 | 1440 | 17 min | 3 |
| expert | 1000 | 2400 | 22 min | 2 |
| evil | 1500 | 3600 | 33 min | 1 |
How the score is calculated
Your score builds up from 0 as you place correct numbers, up to the full base when the board is finished. Then two bonuses are added:
base × (1 + combo bonus + time bonus) × 1.2
- Progress: the live score climbs from 0 to the base as the grid fills with correct numbers.
- Combo bonus (up to +50%): keep a clean run for the full bonus. Each error or hint is a combo break that shrinks the bonus — but it never takes points away below the base.
- Time bonus (up to +50%): beat the normal time and you earn extra, proportional to how much faster you were. Finishing slower than normal costs nothing — there is no time penalty.
- The total is multiplied by ×1.2 and never drops below 0.
Coins
The coins you earn reflect your score — the more points, the more coins (about 1 coin per 20 points, minimum 1). Spend coins in the Shop on hints and Jokers.
Tip: a clean, hint-free solve under the normal time scores the highest. The Daily Challenge is always Classic and fully scored.