A block puzzle game ends when none of your blocks fits anywhere. It rarely happens out of nowhere: a few moves earlier, the board already had one of a handful of problems. Learn to spot them and your games will last far longer.
1. Single holes everywhere
What it looks like: lots of one-square gaps scattered over the board. Why it ends games: only a single square can fill them, and singles are rare. Each hole also stops its row and its column from ever clearing. Fix: before placing a block, check that it doesn't leave a lone empty square next to it. Use small corners and lines of 2 to fill holes you already have.
2. A blocked middle
What it looks like: blocks in the centre of the board with empty space around them on all sides. Why it ends games: the board is split into narrow strips where no 3×3 square or long line can fit. Fix: build from the edges and corners inward. Keep the middle open as long as you can.
3. No room for a 3×3 square
What it looks like: plenty of empty squares, but not nine together. Why it ends games: the 3×3 square is the hardest block. When it turns up, it needs a clear 3×3 area. Fix: keep one corner region free on purpose. If it gets used, clear a line nearby to open it up again.
4. No free line of five
What it looks like: every row and every column has a block somewhere in the middle. Why it ends games: 5-long lines and big corners need long straight runs. Fix: keep at least one row or column mostly empty, and finish half-full lines rather than starting new ones.
5. Too many half-finished lines
What it looks like: most rows and columns are about half full, and none is close to clearing. Why it ends games: the board fills up without anything clearing. Fix: concentrate on one or two lines at a time and clear them.
Learn from each game
When Blockfold shows No space left, take a second before you tap Play again. The block that didn't fit is still in the tray below, and the last few moves usually explain why it had no room. Ask which of the five problems above caused it, and avoid that next time.
In Blockfold, a block that has nowhere to go is drawn faded in the tray. When you see one, your next move should make room for it, usually by clearing a line.
For a full routine, see 10 block puzzle tips, and for the shapes to plan around, see every block puzzle piece.
