Types of Mechanical Puzzles: Slide, Jump, Pack, Cut, Match, Twist
The six types of mechanical puzzles, sorted by what your hands do: slide, jump, pack, cut and rearrange, colour-match and twist, with how to start each.
Riddle10 blog
Articles about solving methods
Cube Counting Puzzles: How to Count Every Cube in a Stack
Count every cube in a stack, hidden ones included. Use a height grid, check by layers and diagonals, then try a worked example and a practice puzzle.
Jigsaw Puzzle Strategy: Edges, Sorting, Clusters and the Last Pieces
Solve jigsaw puzzles in order: edges first, sort by colour and shape, grow clusters, then fit the last pieces by shape. Worked example and practice puzzle.
How to Solve Spot the Difference Puzzles: The Grid Method
Scan both pictures cell by cell, sort changes by kind and check your tally. A six-step method, a worked tile puzzle and a practice puzzle with answer.
How to Solve a Polycube Puzzle: Volume, Colour and Layers
Pack cube pieces into a box with four checks: volume, a 3D checkerboard colour count, awkward pieces first and layer by layer, plus a practice puzzle.
How to Solve a Pentomino Puzzle: Area, Corners and Colours
Fill a board with the 12 five-square pieces. Check area and colour, mark tight corners, place awkward pieces first, then try a worked and a practice box.
Sliding Block Puzzles: Clear the Blocker Chain, Free the Target
Work back from the target: trace the blocker chain, count free cells, move small pieces first. A worked tray, a parking-style grid and a practice puzzle.
Gear Train Puzzles: Which Way Does the Last Gear Turn?
Meshing gears turn opposite ways, so count the contacts. Learn why odd rings jam, how belts change direction, and solve a worked gear train puzzle.
Tangled Cord Puzzles: How to Remove Every Crossing
Move one dot at a time, count crossings in pairs and fix a triangle first. A worked tangled cord puzzle, a practice puzzle and the networks that never lie flat.
Dot-to-Dot Path Puzzles: How to Join Every Dot Exactly Once
Join every dot once in a single path: count partners, fix forced links, use hop-length and arrow rules. With a worked row example and a practice grid.
One-Stroke Drawing Puzzles: How to Solve Them by Counting Lines
Count the lines at each dot to see if a figure can be drawn in one stroke and where to start. Method, worked example, arrow version and practice puzzles.
Counting and Combination Puzzles: How to Count Every Way
Learn when to multiply and when to add, how to count orderings, groups and number splits, and how to avoid double counting, with a worked puzzle.
Process of Elimination in Puzzles: Rule Out Until One Is Left
How to use the process of elimination in puzzles: list options, cross out what fails, and add a guess-and-check step when you stall. Worked grids.
Knights, Knaves and Normals: Three-Type Logic Puzzles
Knights, knaves and normals puzzles with a truth-teller, a liar and a normal who can say either: a case method, a worked example and a practice puzzle.
How to Solve Boat-Placement Puzzles: Find Every Hidden Boat
Use row and column counts and the no-touching rule to find every hidden boat. A clear method, a worked six by six puzzle and a practice grid.
How to Solve Pair-Matching Path Puzzles: Join Every Pair
Join equal numbers with paths that never cross and fill every cell. Learn corner and edge forcing, then try a worked puzzle and a practice grid.
How to Solve Star-Placement Puzzles: Stars That Never Touch
Place stars in every row, column and region so that none touch, even at corners. Five core moves, a worked five by five puzzle and a practice grid.
How to Solve Building Height Puzzles: Count What You Can See
Read edge clues as visible buildings, use the tallest-at-the-edge and cap rules, then follow a worked four by four building height puzzle and a practice grid.
How to Solve Sum Grid Puzzles: Runs, Totals and Digit Sets
Learn the totals that allow only one set of digits, use crossing runs and the no-repeat rule, then follow a worked sum grid puzzle and try a practice grid.
Calculation Cage Puzzles: How to Solve Target-and-Operation Grids
Start with single cells and one-pair cages, list digit sets for sums and products, then use rows and columns. A worked grid and a practice puzzle.