While sitting down at my computer to write a game review I accidentally knock a glass of water over. The contents of the glass splash over our pet cat, giving her a mighty shock. She immediately leaps through an open window and bounds across a busy road. Spotting her, a driver slams hard down on his breaks, causing the truck behind to crash into the back of him.
No serious damage is done to either vehicle but the force of the impact causes a vial in the back of the truck to crack, allowing a deadly virus to escape. Released from captivity, the virus multiplies rapidly. After swapping details with the car driver, the lorry operator continues his journey, oblivious to the invisible cloud of deadly contagions trailing behind him.
By the end of the day, half the population of the country have been turned into mindless zombies. Terrified by one of these slavering human shells, my cat returns to my abode and jumps onto my lap. As I absent mindedly stroke her, an idea for a new top 10 list forms in my mind: Top 10 Chain Reaction Games.
Funded by UK science charity The Welcome Trust and media company Channel 4, this unusual take on the chain reaction genre is aimed at raising awareness of swine flu infection. Its creators describe it as an educational game but there is nothing staid or boring about Sneeze. Far from it, the game is simply great fun. It is also a bit disgusting but, hey, we all like a bit of disgusting occasionally.
The aim of the game is to infect as many people as possible with swine flu. You start each level with one infected person within a crowd of healthy people milling around. Pressing the space bar will make the infected person sneeze. Anyone unfortunate enough to be hit by the sneeze will be infected and, after a short time, will themselves unleash a nasty sneeze, which in turn will infect others.
Things are made a little more complicated by there being three types of people: children (who are easy to infect), adults (hard to infect but they spread the virus to lots of others) and old people (who are also easy to infect but only infect others at a slow rate). The game only has ten levels but those ten levels pack in a lot of fun and challenge. Sneeze can be played here.
This much-mimicked but rarely bettered classic by Danny Miller distils chain reaction game-play to its bare minimum. There are no fancy graphics, unnecessary options and superfluous storyline, and the game is all the better for it. Simply click with your mouse to create an explosion, the idea being that any sphere that comes into contact with the detonation will in turn blow up, setting in motion a chain reaction. Playing games has rarely been as enchanting and relaxing. You can play Boomshine here.
3 Icy Gifts
Icy Gifts takes the core game-play of Boomshine and adds all the extra trimmings that people nowadays expect from a game. So you have a series of achievements to aim at, and also an upgrade path for your explosion. The points you accumulate by completing levels can be spent on increasing the radius of your explosion, giving it a magnetic ability to attract things into it, and so on. Whether all this extra baggage works better than the simple purity of Boomshine is open to question but you cannot deny that Icy Gifts is an intriguing and fun addition to the chain reaction genre. Play the game here.
Nuclearoids isn't a souped-up version of Asteroids or a particularly painful medical condition. No, it's a cool chain reaction game that lets you set off lots of lovely explosions that turn the screen into something resembling a screensaver designed by Jefferson Airplane.
Some Nuclearoids have special party pieces, like creating black holes to pull in nearby objects or setting off cluster explosions. There's a specific task to complete for each level, but if you're not a particularly goal-orientated person, there's still plenty of fun to be had just triggering the chain reaction and watching those Nuclearoids fly. Make things go boom right now by clicking here.
5 Polygonal Fury
Yet another game that has taken its inspiration from Boomshine but unlike many Boomshine copycats, the developers of Polygonal Fury have at least added some new features to differentiate it a little from the original.
For a start, the game includes a variety of different shapes. In Boomshine, you only have spheres. But in Polygonal Fury there are a whole range of different objects, each with its own unique powers. When struck by an explosion, triangles zap random nearby shapes, for example, and squares crash into fellow objects. In later levels, the shapes also become more resilient and may need to be blown up multiple times before they can be destroyed. Play Polygonal Fury here.
6 Star Shine 2
Hurrah! A chain reaction game whose core game-play mechanic is not nicked from Boomshine. The aim of this beautiful, relaxing game is to light up all the stars in the sky. You do this by firing a projectile at one of the stars. This star will not only start shining but also fire out a fragment that in turn could light up another star. Different types of star shoot out fragments at different angles, so you have to think carefully to ensure that your initial shot will end up illuminating all the stars. Play Star Shine 2 here. The original game can be played here.
7 Chain of Fire
Calling all you pyromaniacs out there. Actually scrap that. Pyromaniacs generally like burning inanimate objects. In this game you burn actual people. What are psychopaths who specialise in putting people on fire called? Burniacs? Parch enemies? Pyre-ates? Anyway, if you are such a person, you will absolutely love this game. You get to burn people to your heart's content.
The game plays very similarly to Sneeze, except rather than spreading infection among a group of people, you try to set them all on fire. You start by clicking on a person to set them ablaze, and clicking again to make them run somewhere. Anyone they run into will catch fire and themselves start running around. Chain of Fire can be played here.
8 Infectionator: World Dominator
Most people hide away in their bedrooms when they are suffering from an infectious illness. They don't want to pass their illness on to their friends and family. Not the god-like protagonist of Infectionator: World Dominator - a fun strategy game by Toge Productions that features chain reaction elements to its gameplay.
He loves nothing more than sharing his infectious illness with as many people as possible, and he has at his disposal a particularly insidious infection, one that turns people into zombies. Your task on each level of the game is to infect or kill all the people within 60 seconds. But it is not just the infection that has gone viral. So has the game itself, proving to be one of the biggest hits of 2010. We indeed made it one of our Games of the Year 2010. Play Infectionator: World dominator here.
9 Circle Chain
Like Boomshine but a lot harder, Circle Chain by Emanuel Eferonato is for people who like their chain reaction games to be fiendishly difficult. When you click in Boomshine, you create a nice powerful circular explosion. In Circle Chain, in contrast, all you get are four little projectiles firing out at right angles to each other. And if you are somehow lucky enough to hit another circle with one of the projectiles, the resulting explosion is equally pathetic. Still, the difficulty is half the appeal of the game. Go play Circle Chain here.
10 Flower Reaction
Flower Reaction may not be the first game to feature this chain-reaction style of game play (Boomshine did it long before) but it is certainly one of the prettiest examples in the genre. Combine that with some serene classical music and you have a seriously relaxing and addictive game. Flower Reaction can be played here.