The impact of the Half-Life series cannot be understated, with the success stories of a range of other key titles including Counter Strike, Team Fortress, Portal and even the entirety of the Steam network intrinsically linked to this remarkable franchise.
For a generation of gamers, the original Half-Life was a game that persuaded them to upgrade their PCs, and made a game about more than merely action.
Half-Life was not the first to bring scripted storytelling to a shooter, but its incredible set pieces and sense of humour – not to mention perhaps the most iconic beginning of any game ever – means that it lives on in both the memories and thousands of pale imitations.
Who could forget the sound-sensing alien or the moment when you are deprived of your weapons and dumped in a waste compactor?
What about the moment when the soldiers you have been battling to find turn on you, in a truly stupendous plot twist, or simply riding the mono rail to your job as you first meet the iconic and silent hero Gordon Freeman for the first time?
What is for certain is that many believed that Valve – a company set up by two ex-Microsoft employees – would struggle to top their classic.
Counter-strike and sequel
Indeed, if anything the game was transcended by, of all things, a mod of the game that pitted teams of good against bad in a game called Counter-Strike. It quickly became one of the most played online games of all time, and for years the most important professional team gaming title of choice.
In May 2003, expectations of a sequel reached fever pitch, and at E3 the first glimpse of the game was revealed. Amazingly, it managed to surpass what the fans could even have dreamed of – with the source engine showing off game physics that changed the nature of the whole industry.
Of course, the course of true love never runs smooth, and Half-Life 2 hit a major hurdle when it was discovered that the company computers had been hacked into and a major part of the source code leaked.
The discovery set the game back significantly, and it was eventually released to mass critical and public acclaim in November 2004.
To play the game, users needed to install the Steam application, giving Valve an immediate huge customer base which, after getting over early disgruntlement at being forced to use the system, became hugely important in evolving the PC digital gaming market
Orange box and Portal
Taking the slightly odd, and perhaps regrettable, decision to work on small chapters as sequels rather than a standalone next game, Valve nevertheless kept their audience happy with well-received add ons and the phenomenal Orange Box compilation, which included the first two chapters, Team Fortress 2 and a little game called Portal.
Of course, the latter is now a hugely important game IP in its own right, and Team Fortress 2 remains one of the most played online games. It was almost certainly the greatest compilation of titles ever released.
Portal 2 is considered to be part of the Half-Life universe, but it's been five years since the release of Half Life 2 Episode 2, and the gaming world has changed hugely in that time.
Despite this, the legacy of the Half-Life series means that Half-Life 3 is perhaps the most eagerly anticipated game of its generation.
Let's be honest, it remains unlikely if not implausible that we will see the game at Gamescom this year; but as and when it does stick its head above the parapet expect the gaming world to go into meltdown, and a whole new generation attach themselves to a legendary franchise.
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