Falling Blocks

• Keep the top of the stack flat. A flat surface takes nearly every shape without leaving a hole underneath; a jagged one takes two or three. Most games end because the stack grew teeth, not because it grew tall.
• Never bury an empty square. A block laid across a gap seals that row until you have cleared every row above it. One buried hole costs more than three clumsy placements.
• Keep one column open as a well, usually at an edge, and feed everything else around it. The long straight piece is the only shape that fits a one-wide gap, so the well is where you cash it in. There is no bonus here for clearing four rows at once, so the well is about staying tidy rather than about points.
• Look at the preview and place the current piece so it does not spoil the landing place for the next one. That single habit is most of the difference between a short game and a long one.
• The S and Z shapes are the awkward pair: laid on a flat surface they always leave a gap underneath. They sit flush on a single step, so if your stack is perfectly level it is worth keeping one deliberate step in it.
• Turn the piece before it is against a wall. The game only turns a shape if the turned shape fits where it is standing, and it does not nudge it sideways to make room, so a rotation next to a wall can simply do nothing. Move one column in and turn it there.
• A piece rests on the stack for about half a second before it locks, so a late nudge left or right still works. The space bar is the exception: it drops the piece and locks it immediately, with no moment to change your mind.

This is one of the livelier games on the site, and it is honest to say so plainly. The pieces fall on a clock, the clock gets quicker as you clear lines, and it never slows down again. That suits some hands and not others. If you would rather nothing moved until you moved it, Sudoku and Mahjong will wait all afternoon, and Block Puzzle is the same idea of fitting shapes together with no clock at all.

What does help here: Pause is a real pause. The Pause button, the Escape key or the letter p freezes the board with PAUSED written across it, and nothing moves until you press again. The playing area is ten columns wide and twenty rows deep, drawn large, and the falling piece is shown twice over — solid where it is now, faint where it will land. At the start each piece falls about one row every half second, and that quickens by roughly seven per cent for every ten lines you clear.

Two limits worth knowing. Nothing is saved: reload the page and you begin again at zero, with no record of a best score. And there is no sound at all in this game, so there is nothing to mute. On a keyboard, the left and right arrows move the piece, the up arrow turns it, the down arrow moves it one row and the space bar drops it. On a touchscreen, slide a finger sideways to move it, tap the board briefly to turn it, and swipe firmly down to drop it.

The pieces are older than any video game. They are tetrominoes: the shapes you can make by joining four squares edge to edge. The mathematician Solomon Golomb coined the word polyomino for the wider family in a talk to the Harvard Mathematics Club in 1953, and wrote the standard book on them in 1965. There are five such four-square shapes if you are allowed to flip them over, and seven if you are not. A shape falling down a screen can be turned but never flipped, which is why this game, and every game of its kind, has exactly seven pieces.

The falling-block puzzle itself was written in Moscow in 1984, by a researcher at the computing centre of the Soviet Academy of Sciences, on a machine that could barely draw a picture. Copies spread on floppy disks across the city and then across Eastern Europe before anyone sold a single one; the first commercial release came in January 1988, and within a few years the ten-wide field and the seven shapes were on nearly every home computer and handheld in the world.

It is also genuinely hard, and not only because it is fast. In 2002 Erik Demaine, Susan Hohenberger and David Liben-Nowell proved that even if you were handed the whole sequence of pieces in advance, and given unlimited time to think, working out the placements that clear the most rows is NP-complete: one of the class of problems for which no efficient general method is known. Nobody plays this perfectly, so there is no need to feel slow.

This is a self-hosted, open-source version of Falling Blocks (source), used under its MIT licence and hosted here so it loads fast and shows no third-party adverts inside the game. Browse all of our free games.