Block Stacker
Play Block Stacker in your browser. Stack falling blocks, clear lines, and rack up a high score.
How to play
- Click Start to begin, then use ◀▶ to move the falling piece left or right.
- Press ↑ or Space (or ↻ button) to rotate the piece.
- Press ↓ to soft-drop the piece faster into place.
- Fill a complete horizontal line to clear it and earn points.
- Click Pause to freeze the game; click Start again to restart.
Press Start, then use arrow keys or on-screen buttons to move/rotate pieces. Clear complete lines to score. Up or Space rotates.
How it works
Block Stacker is a Tetris-style game where geometric pieces called tetrominoes fall from the top of the playfield one at a time. You rotate and position each piece to fit into the stack below. When a horizontal row is completely filled it clears, freeing space and awarding points.
The game ends when the stack of uncleared blocks reaches the top of the playfield. Pieces fall faster as your score increases, demanding quicker placement decisions.
Use left and right arrow keys to move the falling piece horizontally, the up arrow to rotate it, and the down arrow to soft-drop it faster. Many versions include a hard-drop key (spacebar) that instantly places the piece at the lowest valid position.
Keeping the playfield flat and low is the core principle. Tall irregular stacks leave gaps that are nearly impossible to clear, whereas a flat surface gives every new piece a viable landing spot.
Worked example
Clearing a four-line Tetris
- Build the playfield with a deliberate single-column gap on the far left or right.
- Fill rows 1 through 4 across all other columns, creating four nearly-complete rows.
- Wait for a vertical I-piece (the long straight piece) to appear.
- Drop the I-piece into the gap column to clear all four rows simultaneously for maximum points.
Four rows cleared at once, the highest-scoring single move in the game.
Common mistakes to avoid
- Building tall towers on one side instead of keeping the playfield flat, which leads to uncleared gaps.
- Ignoring the next-piece preview and placing the current piece without accounting for what is coming.
- Rotating pieces repeatedly out of habit rather than committing to a placement, wasting time as speed increases.
Key terms
- Tetromino
- A game piece composed of four square blocks joined together in one of seven possible shapes.
- Line clear
- Removing a completely filled horizontal row, which awards points and lowers the stack.
- Hard drop
- Instantly placing the current piece at the lowest available position in its current column and rotation.
Frequently asked questions
- How do I rotate?
- Press Up arrow or Space (keyboard) or the ↻ button on mobile.
- Does speed increase?
- Speed is fixed in this version — focus on clearing multiple lines at once for big scores.