Spheres of Chaos is a colourful and superbly-playable Asteroids tribute originally written for the Acorn Archimedes by Iain McLeod and Matt Black and self-published in 1993.

You control a small, grey spaceship that starts off in the middle of the screen, which can move around using thrusters and can also shoot out of its nose at the front of the ship. Large spherical objects, called “common aliens”, move around the playfield and these break up into smaller spheres when shot by the spacecraft. The aim of the game is to clear each screen of common aliens and to rack up as many points as possible before you lose all of your three lives.

If you take too long to clear a screen alien spacecraft will appear and start shooting at you. Weird alien structures can also appear and these will break up if shot, sometimes launching homing missiles at you, or ejecting pulsating substructures. There are bomber craft that lay mines in the playfield, and also alien spacecraft that spiral around or home in on you making survival more difficult.

Black holes will occasionally appear on the playfield and these will attract the spacecraft to its doom, so must be avoided at all costs. Multiple black holes can make life very difficult for the player – especially if there’s a lot going on on-screen. Black holes will also suck up enemies too, so they can also make the playfield easier to navigate at times.

Spheres of Chaos is a very nice-looking game with dazzling use of colour and simple, but beautiful, graphics. But what make it such a compelling game to play are the refined controls. Thrusting around and blasting things feels good due to the ship’s inertia and thrust rate. If you need thrust quickly – to escape from a tricky situation – you get it. If you’re close to a black hole and need thrust to escape – you get it. The ship turns quickly, so most situations can be dealt with. That said: on occasion I did want reverse thrust, but in those cases it was as I was travelling at speed towards an enemy that was moving towards me and I knew there was no escape.

As the levels change the colour of the background changes, and explosions are punctuated with colour flashes. Combine this with colourful pixels, waves, circles and trails coming from objects and explosions and you get a game that looks pretty amazing when it’s in full flow.

Spheres of Chaos was re-programmed by the original author and re-released for free on Windows and Linux in 2012, and it’s still available to download now (at the time of writing). The re-programmed version is very good, but I do in fact prefer the original RISC OS version because of its beautiful pixel graphics. In my humble opinion it’s one of the best games on the Archimedes.

See also: The King of Grabs Archimedes Special

More: Spheres of Chaos on Wikipedia