Some of the features:
1. Pink sokoban cube theme
2. Axes that swivel and/or disconnect
3. Black/white ordering
4. Look at image 2. That level is a maze
5. Yin/Yang pairing
Update 12/30/17: I finished the game. There are 65 levels plus one spelling puzzle at the end.
Other games from Maciej that you must download.
The annual PAGY Awards are fast approaching. Each year, I nominate the best Puzzle App Games of the Year on December 30. The winners will be named December 31.
Note: the PAGY Awards are very subjective. (Just like the Oscars, the Grammys and the Pulitzers.) The first purpose is to draw more people to the joy of puzzles. The second is to recognize the indie gamers who put forth their best creative efforts. Sadly, many of these games are unprofitable. It's the elephant in the room. But we hope they continue.
To be sure, I have play tested every single game thoroughly. A constant regret of mine: overlooking a puzzle. If I've missed a worthy game, send me a note, and I'll include it for 2018.