Spheres of Chaos is a space shooter created by Iain McLeod, the basic gameplay being similar to the game Asteroids. The game uses very bright, psychedelic colours and patterns, with many enemies on screen at once. The audio is similar to that of Robotron: 2084 and Defender. The game was originally written for RISC OS on the Acorn Archimedes. Ports exist for Linux, Windows and PS2 Linux.

The player controls a small grey spaceship and levels are completed by eradicating all enemies from the screen. The difficulty and amount of enemies increase along with the level number. Enemies will typically split up into smaller versions when hit. Black holes also appear during gameplay and either attract or repel the spaceship. Many black holes at once can mean that space becomes unnavigatable.

Some enemies will provide power-ups when defeated. The colour of the power-up when found will affect the ability of the power-up.

There are various options which can be modified to change features such as the amount of enemies and power-ups as well as in-game visuals. The game can be played in single player or in multi-player with up to 8 players.