How to Play Blockdoku
Blockdoku is a block fitting puzzle on a nine by nine board. Three pieces sit in a tray under the grid, you drop them wherever they fit, and filling a row, a column or a three by three square clears it away.
Nothing is timed and nothing chases you. The only pressure is space, because the blocks never rotate and the board only empties when you clear something. Play well and a game lasts as long as you want it to.
Play BlockdokuHow to play Blockdoku
- Drag a piece from the tray onto the board. It drops wherever it fits whole, and the board shows you the landing spot before you let go.
- Fill a full row, a full column or a full three by three square and those cells clear.
- Clear more than one at a time for a bigger score. A single piece can finish a row, a column and a square together.
- The tray refills only once all three pieces are gone, so plan the set rather than the piece.
- The game ends when none of the three pieces in the tray fits anywhere on the board.
The rules in short
- The board is nine by nine, marked into nine squares like a Sudoku grid.
- Pieces cannot be rotated or flipped, so what you see in the tray is what goes down.
- A piece has to fit entirely on empty cells.
- Rows, columns and three by three squares all clear.
- You score for every cell you place and much more for every line you clear.
Tips that keep a board alive
Place against what is already there. Blocks tucked along an edge or against another block leave one big open area instead of several small ones, and a big open area is what the awkward pieces need.
Keep room for the three by three block. It is the piece that ends most games, so check before every move that somewhere on the board could still take it.
Single gaps are the enemy. A hole with blocks on all four sides can only ever be filled by the one by one piece, and that piece might not turn up for a while.
Look at all three pieces before you move the first one. The order you place them in often decides whether the third one fits at all.
Keep a square nearly full on purpose. One piece then clears a square, a row and a column together, which is where the big scores come from.
Frequently asked questions
Can I rotate the blocks?
No, and that is the whole puzzle. A piece goes down exactly as it appears in the tray, so the question is always where it fits rather than which way round it sits.
What clears a line?
Filling every cell of a row, every cell of a column, or every cell of one of the nine three by three squares. All three count, and they can happen on the same move.
When does the game end?
When none of the three pieces in the tray can be placed anywhere. There is no way to skip a piece, so the board has to keep room for whatever turns up.
Is there a way to win?
There is no finishing line. You are playing against your own best score, which the board remembers between visits.
Is it the same as Sudoku?
Only the grid is. There are no numbers and no deduction, but the three by three squares clear the same way they matter in Sudoku, which is where the name comes from.