The Nintendo tumbler puzzle, also known as the Ten Billion Barrel, is a mathematical puzzle in the style of Rubik's Cube. It was invented by Gunpei Yokoi of Nintendo and is covered by U.S. Patent 4,376,537.

It consists of a "cylinder" of transparent plastic divided into six levels, together with a black plastic "frame". The frame consists of upper and lower discs that are joined together through the middle of the cylinder.

The top and bottom levels of the cylinder form a single piece, but between them are two rotatable pieces each two levels high. Each of the four central levels is divided into five chambers each containing a coloured ball. The top and bottom levels have only three chambers, containing either three balls or three parts of the frame depending on the relative position of frame and cylinder.

The balls in three of the five resulting columns of chambers can be moved up or down one level by raising or lowering the frame relative to the transparent cylinder.

The object is to sort the balls, so that each of the five columns contains balls of a single colour.

External links

• http://www.geocities.com/jaapsch/puzzles/nintendo.htm (photos and solution)
• http://www.smartbytes.co.uk/Tumbler/ (solution)