About Block Stack
Block Stack is a falling-block puzzle on a 10 by 20 well. Seven kinds of four-square pieces drop from the top one at a time, and your job is to slot them together so that horizontal rows fill completely and disappear before the stack reaches the top.
How to play
- Pieces are chosen completely at random from the seven shapes each time, so the same shape can come several times in a row and a long wait for a particular piece is possible.
- A piece locks when it cannot fall any further. Any row that is completely full is cleared and everything above it drops down.
- Clearing 1, 2, 3 or 4 rows at once scores 100, 300, 500 or 800 points, multiplied by your level.
- Your level is 1 plus every 10 lines cleared. The multiplier uses your line total after the clear, so the clear that takes you from 9 to 10 lines already pays at level 2.
- Gravity starts at one row every 0.7 seconds and gets 0.07 seconds faster each level, reaching its top speed of one row every 0.08 seconds at level 10.
- Soft drops and hard drops do not earn extra points. There is no hold slot and the next piece is not shown.
- The game ends when a newly spawned piece cannot fit at the top of the well.
Controls
- Keyboard: Left and Right arrows move, Up arrow rotates clockwise, Down arrow drops one row, Space hard-drops the piece to the bottom.
- On-screen buttons below the board do the same five actions for touch screens: left, rotate, right, down and drop.
- A faint ghost piece shows exactly where the current piece will land if you hard-drop it.
- Rotation tries small sideways nudges of one or two columns if the piece would otherwise hit a wall, so you can rotate pieces that are pressed against the edge.
Tips and strategy
- Keep the surface of your stack as flat as possible. Bumpy surfaces leave awkward gaps that only one shape can fill.
- Leave one column empty at the side for the long straight piece. Four rows at once earns 800 times your level, far more than four single clears (400).
- Because pieces are fully random and there is no preview, do not build a setup that depends on one specific shape arriving soon.
- Use the ghost piece and Space to place pieces quickly at higher levels; waiting for gravity wastes time you will need later.
- Pressing Down when a piece is already resting locks it immediately, which is useful when you are sure of the placement.
- Rotation only goes one way, so a piece that needs a counter-clockwise turn takes three presses; plan rotations early while the piece is still high up.
Background
The falling-block puzzle was created by Alexey Pajitnov in 1984 while he worked at the Dorodnitsyn Computing Centre of the Soviet Academy of Sciences in Moscow. The pieces, called tetrominoes, are every shape you can make by joining four equal squares edge to edge, and there are exactly seven of them if mirror images count separately. The genre spread across the world in the late 1980s, and the basic loop of fitting shapes together and clearing lines has been reused in countless puzzle games since.
Questions
- How is the score calculated?
- Only line clears score. One line is 100, two is 300, three is 500 and four is 800, each multiplied by your current level. Dropping pieces faster does not add points.
- Does it get faster?
- Yes, every 10 lines. The drop interval goes from 0.7 seconds at level 1 down to 0.08 seconds at level 10, and stays there after that.
- Can I see the next piece or hold one?
- No. This version has neither a next-piece preview nor a hold slot, which makes it a little harder than many modern versions.