Zack’s Ring – World’s Most Difficult Ring Puzzle

Please note: Despite its name and its origin as a puzzle ring, Zack’s Ring is not a wearable ring and will not fit on your finger. Due to the complexity of the mechanism, it is not possible to 3D print a functional version small enough to be comfortably worn as jewelry. The actual size of the puzzle is 112 × 109 × 46 mm.

Zack’s Ring has a very special origin story. The puzzle was originally commissioned as a one-of-a-kind puzzle ring for a marriage proposal. The request was simple: create something unique, beautiful, and extremely difficult to solve.

Oskar came up with a design consisting of six interlinked rings arranged in a loop, forming a shape somewhat reminiscent of a Star of David. Designing it was a challenge of its own, as most configurations either came apart too easily or didn’t come apart at all. The final design was inspired by earlier work by Bram Cohen.

The puzzle comes fully assembled. Your first challenge is to take it apart.

But disassembly is only the beginning.

Once taken apart, the six rings are still connected to each other, leaving you with an intimidating chain of interlinked pieces. Now you have to figure out how to manipulate all six rings back into their original shape.

This is an extremely difficult puzzle, and reassembling it may be one of the hardest challenges in your puzzle collection.

Think carefully before you take Zack’s Ring apart.

Designer: Oskar van Deventer
Size: 112 × 109 × 46 mm
Difficulty: Extremely difficult