How Grid Lock works
Each round shows a grid and a set of shaped blocks, much like Tetris pieces. You rotate the blocks, drop them into the grid and take them out again when they will not fit, until every square is covered. Then the next, harder board appears. There are 9 boards and 3 minutes for the game, and the aim is to clear each one as quickly as you can.
Boards are drawn at random from sets of equal difficulty, so two candidates rarely see the same one, and the game shows how you are doing as you play. Grid Lock is in every version of Cognify, and it is the game behind the Problem Solving sub-score in the standard report.
People who play video games more often score slightly higher on Grid Lock. The effect is small, and the tutorial before the game, which you can repeat as often as you like, is there to close it.
How to solve a Grid Lock board
Use the same order on every board:
- Start with the piece that has the fewest places it can go, usually the largest or an awkward L or T.
- Fill corners and edges before the middle. Only a few pieces can reach a corner square, so settle it early.
- After each placement, look for a gap nothing can fill: a single cut-off square, or a space narrower than every piece left. If you see one, lift the last piece straight away.
- Turn a piece in your head before you pick it up, so you place it in one move.
- Keep straight pieces for last. They fit more spaces than any other shape.
Worked example
The board is 4 squares wide and 3 high, 12 squares in all. The pieces are a 2 by 2 square and two L pieces, each a line of three with one square turned off the end. 4 + 4 + 4 = 12, so every piece is used.
Put the square in the top-left corner. Lay the first L along the bottom row, three squares from the left, with its end square turned up into the third column. The second L fills the rest: down the right-hand column, with its end square turned in at the top. The board is full.
Had you laid the first L along the bottom from the second column, with its end turned up into the right-hand column, the bottom-left square would be cut off on its own. No piece fills one square, so that is the moment to lift the L and try again.
Tips for the real Grid Lock
- Repeat the tutorial until rotating, placing and removing pieces takes no thought.
- The 3 minutes cover all nine boards, so do not let one stalled board eat the time for the rest.
- Lift a piece as soon as it creates a gap nothing left can fill, rather than building around it.
- If you rarely play puzzle games, spend some time on block-fitting puzzles in the days before.
- On a laptop or desktop, use a mouse. Cognify asks for one.
Practise Grid Lock on CogniPrep
Our Grid Lock gives you 8 boards on one 8-minute clock. Boards run from rectangles to crosses, rings and diamonds, cut into pieces of up to five squares, and every board has an exact solution. Drag a piece on, or tap it and tap a square; rotate it before you drop it. The board moves on once it is full, and you can reset it or skip it. Your score out of 100 weighs boards solved most, then how few placements you needed, then speed. The real game gives you far less time per board, so learn the method here, then push for speed.