Kerslide
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The shift rule, explained with pictures
Every clear in Kerslide moves the whole board one cell. Here is exactly how it works, with before-and-after diagrams.
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Most grid puzzles treat a cleared line as a reward: the space is free and nothing else changes. Kerslide adds one rule on top, and that rule decides almost every interesting moment in the game. This guide walks through it step by step with board pictures, so you can predict every move before you make it.
The rule in one sentence
After you place a piece, every complete row and every complete column is removed at the same time; then, if a row was removed, every remaining block moves one cell right, and if a column was removed, every remaining block moves one cell down. Blocks that move past the right or bottom edge are gone for good. There is no wraparound.
Example 1: clearing a row
In the first picture, the fifth row is one cell short. Dropping a single block into the gap (outlined) completes it.
Three things happened at once. The full row disappeared. Every other block slid one cell to the right: the blue pair near the top moved from the third column to the fourth, and the green pair moved toward the right edge. The two red blocks were already in the last column, so the shift pushed them off the board. You removed eight blocks with the clear and two more with the shift, without ever filling their lines.
Example 2: clearing a column
Columns work the same way, only downward. Here the first column is waiting for one block in the bottom-left corner.
The column clears, then the whole board drops by one row. The purple pair at the bottom was on the last row, so it falls off the board. The other blocks keep their shape and their position relative to each other; they are simply one row lower.
Example 3: a row and a column together
A single piece can complete a row and a column at the same time, for example an L shape that fills the last gap of the bottom row and the last gap of the right column. Both lines clear together, and the two shifts combine into one diagonal move: every survivor moves one cell right and one cell down. Anything on the right column or the bottom row afterwards leaves the board.
How far does the board move?
Always one cell, no matter how many lines you clear. Clearing three rows at once still moves the board one cell to the right, not three. That keeps the result easy to read: the board is either unchanged, one cell right, one cell down, or one cell diagonally down-right.
Can a shift start a chain reaction?
No. After a right shift the leftmost column is always empty, and after a down shift the top row is always empty, so a line can never be complete straight after a shift. Each placement resolves in exactly one clear and at most one move. You never have to worry about cascades you did not plan.
Why the rule changes how you play
- Blocks drift toward the bottom-right. Every clear nudges the board in that direction, so the top-left corner is where fresh space keeps appearing. Keep it open for long pieces.
- The edges are exits. A block sitting on the right column leaves with the next row clear; one on the bottom row leaves with the next column clear. Awkward leftovers near those edges are temporary.
- Half-built lines move. A row you are building keeps its shape when another row clears, because the whole board moves together. But a row clear shifts your nearly complete column one cell to the right, which can leave it next to a different set of blocks. Look at where your lines will be, not where they are.
Use the preview
While you drag a piece, Kerslide highlights the lines that would clear and shows the direction the board will move. When in doubt, hover the piece over a few spots and compare the results before letting go. There is no timer, so the extra second is free.
Next: learn how clears turn into points in the scoring and combos guide, or see every piece in the piece guide.
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