Oxyd

You control a black orb that is trapped in a puzzle-like labyrinth. A level is called a landscape and there are 200 landscapes to solve. The main gameplay element consists of opening the so-called oxydstones. You can bump against an oxydstone and a colored symbol will appear. Uncover two of the same colors and they will stay open, making it a memory-like game. Open all oxydstones to solve a landscape.

To make things more interesting there are walls, pitfalls, quicksand, one-way walls, breakable tiles, reflecting lasers (for Deflektor-like puzzle solving), movable blocks (for Sokoban-like puzzle solving), tiles that crumble away when you roll over them, doors, switches, etc. Some of the landscapes contain items that you can pick up and use. Items include pieces of paper with hints, umbrellas that give you the ability to float, bombs to blow up walls, or a spring to jump across gaps.

To mix up the gameplay, every tenth landscape is a meditation landscape where you simultaneously control several green orbs. Manoeuvre each of the orbs into a pit to solve these landscapes.