do we ever get any idea as to what gordon looks like? is it the guy on the front case of the orange box?
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oh and also can someoen give me a very simple explanation of the story of half life 1, there was some references in the game which i assume where to half life 1 but obviously i didn't understnad what they were talking about
Yes, he's the guy with a beard and big plastic glasses.
In halflife 1, you're a new science lab employee for a company called Black Mesa. The day you go in there is a 'big experiment' and you're the guy who has to don the hazard suit and go into the test chamber to conduct the hands-on parts of the experiment.
This basically involves pushing a crystal into a big beam and then all hell breaks loose. The result of this experiment as far as i can tell is a tear between earth and the world/dimension where the vortigaunts come from appears in space with a world call Xen in the middle.
You fight your way through some aliens and then the army arrive, who everyone believes were coming to help but are in fact there to clean up any trace of the accident - including the survivors.
The scientists rely on Gordon to get to the 'Lmabda complex' as they will be the only ones who know how to stop the disaster, and on your way you need to launch a rocket (familiar?) in order to aid the science team in dealing with the situation.
After some time the Army start to lose the battle and pull out of black Mesa, leaving the area to be the staging ground of a full scale invasion by the aliens. At this point you arrive at the Lambda complex, there they tell you that the aliens are in fact controlled by one entity, the Nihilanth, and killing that will stop the invasion. However to do this they need to teleport you into the border world, Xen, where the Nihilanth resides as he stages the invasion.
You go into Xen, kill the Nihilanth and at that point you are plucked from time by the Gman, who has been watching you throughout the disaster, who gives you the option of working for him, or dying. In order for HL2 to occur, Gordon clearly chose to work for him.
NOW - the theoretical part. I believe the Nihilanth was in fact a creation of the combine, who used it to enslave the Vortigaunts who are now free, like they attempt to use Breen in order to control humans. The killing of the Nihilanth, their first attempt at invading and controlling earth, prompted them to launch a full scale invasion of their own between the events of HL1 and HL2. The Gman actually put Gordon in stasis until the moment was right and then placed him back on earth in the train, and then HL2 begins.
[EDIT] Not very simple explanation i know, but i got carried away.