Z-Cube Metallic 15 Numbers Klotski Puzzle

Metallic 15 Numbers Klotski Puzzle

This is the classic 15 puzzle in a silver Metallic version. The 4x4 board has 15 numbered tiles and one empty space. You slide the tiles into the empty space, and the goal is to arrange the numbers in order from 1 to 15, with the empty space in the bottom right corner. This number sliding puzzle has been known since the 19th century and is one of the most recognizable Klotski-type puzzles.

How do you solve the 15 puzzle?

You can understand the rules in a few seconds. Your first solve will take some figuring out, though, because every move shifts tiles that sit next to each other. The most popular method starts with the top row (1-4) and the second row (5-8). You then solve the two bottom rows column by column: first 9 and 13, then 10 and 14, and finally 11, 12 and 15. The last two tiles in a row usually take the most thinking. You have to place them together without breaking up what you have already solved.

Once the method becomes a habit, the 15 puzzle starts to feel like speedcubing. What counts is recognizing the pattern, planning a few moves ahead and sliding smoothly without unnecessary moves. Many people solve it against the clock, even though it is not a WCA event.

How do you scramble the puzzle?

A few dozen random slides are enough to scramble it. Any position you get this way can be solved. However, you should not take the tiles out and put them back in a random order. Half of all possible 15 puzzle positions are mathematically unsolvable, so after this kind of "scrambling" the puzzle may be impossible to solve.

Who is it for?

The 15 puzzle is a great choice for people who enjoy logic puzzles but don't want to learn cube algorithms. For a child, it is a puzzle with simple rules that teaches move planning and patience. For cubers, it is a change from cubes: it takes up little space on your desk and you can solve it during a short break.

Specifications

• Type: number sliding puzzle (15 puzzle, Klotski)
• Board: 4x4, 15 tiles numbered 1-15 and one empty space
• Color: Silver