Oxyd

DongleWare Model

Oxyd's commercial model was named 'DongleWare' by its developers. The game is freely distributable - unlike most shareware, the game is a complete version, and you can play freely the 10 first levels. After level 11, there are coded stones blocking the way so you can't complete the levels. In order to remove the coded stones, you have to use a code. The game is free but the 'Oxyd Book' containing the codes (and mainy clues/tips for the harder levels) was sold at a 'full commercial game' price.