How to play

Blocks made of four squares fall into a tall box, one after another. Slide each one left or right, turn it, and drop it so that it fills a gap. Every row that is completely full disappears, and everything above falls down. The more rows you clear at once, the more points you score, and clearing four at once scores the most. After every ten rows the level goes up and the blocks fall faster. The game is over when the stack reaches the top. A faint copy of the block shows where it will land, and the next two blocks are shown on the right.

On a keyboard: the left and right arrows move, the up arrow (or X) turns clockwise and Z turns the other way, the down arrow drops faster, the space bar drops the block at once, C stores the block in the Hold slot (and swaps it with the held one next time, once per block), and P pauses. On a phone or tablet, use the buttons under the board.

Tips

Keep the surface of the stack as flat as you can and avoid holes you cannot reach. Leave the far-left or far-right column open and wait for a long straight block to fill it, clearing several rows together. Look at the next blocks before you place the current one, and use Hold to save a useful block for later. When the stack gets high, stay calm and clear single rows to survive rather than going for big combos.

Is my score saved? Only your best score, on this device.