Games reviews: La Ora Stelo
 La Ora Stelo was chosen by Games as the best puzzle of the year 2010. Here's reviewer Robin King's write-up from the December 2009 "Games 100" Buyer's Guide to Games: LA ORA STELO Designer: Jacques Ferroul We've seen and enjoyed many polyform puzzles over the years. In a nutshell, these puzzles are sets of pieces composed of multiples of some basic geometric figure or figures. La Ora Stelo uses two triangles of side lengths 1/1/phi and 1/phi/phi. Each piece consists of up to three triangles joined edgewise in all possible combinations. Phi, an irrational number, is called the golden ratio. It has many interesting properties, the most relevant one here being that you square it by adding one. This property enables the pieces to fit together in many fascinating ways, forming pentagons, decagons, stars, and a multitude of others that may be found on Ferroul's website, http://tetrapentos.over-blog.com/article-16069070.html. Your patience in exploring this beautiful puzzle will be abundantly rewarded.      —RHK

 La Ora Stelo received nearly half a page of description, with a nice color photo, in the October 2009 issue of Games: LA ORA STELO Designer: Jacques Ferroul Players: 1 La Ora Stelo is a remarkably novel polyform puzzle, with pieces based on two types of isosceles triangles whose side lengths are related by the golden ratio. The golden ratio is an irrational number known as phi (approximately equal to 1.61803...), and has more interesting properties than you could shake a slide rule at (anyone remember those?). When up to three of these triangles are combined edge-to-edge in all possible ways, they form a set of 32 tiles called polyores. Phi is very common in formulas relating to pentagons, so it is no surprise that this set rests in a pentagonal tray. It also has five small black tiles to fill the center. At least nine other sizes of pentagons can be constructed with a subset of all the tiles. Jacques Ferroul got the idea for this remarkable set when he attended a friend's funeral and meditated on a large gold star in the church. He now has a website (http://tetrapentos.over-blog.com/article-16069070.html) on which you can find a more detailed description of this set, and links to scores of puzzles—such as arranging the pieces to form a perfect star—that will keep you fascinated and busy for a very long time. Warning:  This is not a puzzle for beginners. It demands that solvers keep very careful track of side lengths and various angles on the road to finding solutions. Experienced puzzlers will be intensely challenged but well rewarded for their efforts.      —Robin H. King