We recommend:Puzzle Contests

Kadon enthusiastically endorses a puzzle contest on the Germany-based Bricks website, a vast collection of sliding block puzzles you can download (in zipped files) to play. You can choose any of 10 languages. It works on all versions of Windows only, no other platforms. All levels are still available, since its launch in 1998. The current contest challenge changes bimonthly. A World Ranking List of winners' stats is included. Andreas Rottler is in charge. Visit the Bricks site to see the current contests and deadline for entries, and to participate in their forum. It's elegant and awesome.


Pentomino Competitions
A classroom teacher, Odette De Meulemeester, and her students at the school, K.S.O. Glorieux Ronse (Belgium), in 1999 created a delightful website with diverse pentomino competitions that attracted an international audience of pentomino lovers. (Select your preferred language.) An early challenge was to enclose the largest area (maximum, 175) on a cube. See a sample at left. Their Records page has names of top solvers. The competitions ran for 50 episodes, ending with a special 50 design by Kate Jones. The winning design by Peter Jeuken earned him the award of the special "50" edition of our Poly-5 puzzle. Although Odette retired in 2011, the students continue wonderfully to tend and expand the site as part of their math and technological education, under director Eddy Moreau. Have fun trying your hand at their elegant challenges. Kate also contributed Challenge No. 34, with minimum and maximum perimeters based on the cool cover design of the Quintillions booklet.

Recently added pentomino challenges are here:

The Yin-Yang Pentominoes project team was the winner of our Gamepuzzles Annual Pentomino Excellence award for 2012. See the story about it also on our Awards page.


Kadon contests
Other contests of our own are featured, sometimes hidden, throughout the gamepuzzles website. Some award prizes, some only fame. Most are also listed in our Site Features page here:   Other Amusements. The following challenges are not yet exhausted and remain open to the world (links open in new window):
  • Arc Angles—form one closed matched loop of all 25 tiles, with the minimum enclosed area.
  • The 25-Holes Challenge— fit thirteen Vee-21 tiles (V-trominoes) rigidly into their 8x8 tray with no slipping or sliding. New solution wins a silver dollar (up to 25 winners). The 37 and 40 holes are also still unsolved and will win a prize.
  • The Alphabest Challenge—use the 26 letters of the alphabet once each to form a crossword puzzle in the smallest grid. Beat 42 and win a prize.
  • The Maximum-Squares Challenge— arrange the 16 Chasing Squares tiles to form 24 or more "traceable" squares. Exceed 26 and win a prize.
  • Cornucopia—form progressively longer rectangles with a 17-piece subset of Sextillions in 15 steps. New solutions win fame and a small prize.
  • The Octo Clock—arrange 8 numbers as a clock face to meet goals.
  • The Mini-Quiz series—we've published 8 so far, all still open. No one has fully solved Quiz No. 6. We are curious and curiouser...
  • Rhombiominoes—connect all pieces of same color; new solutions win prize.
  • Poly-5 Perimeter—fill the border with a maximum of pentominoes. New solutions with only 4 non-pentomino edges win a prize.
  • Ten-Yen Enclosure—surround one color with the other two, in the smallest or longest perimeter. New solutions win fame.
  • Triangule-8 Sprouts—form 25 sprouts or prove that 24 is the maximum possible.
  • Trio in a Tray—separate two colors completely. New solutions win a prize.
  • Vee-21, the Three-Color Problem—the search for more solutions of maximum color separation.


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