Experiment gone horribly awry? Aliens planning to destroy the earth? The blight of extra-dimensional aliens, Gordon has caused more damage to an alien race than Master Chief and Duke Nukem combined. With just a crowbar.
Dispite many people's claims that Gordon Freeman is death incarnate, born in the underworld and bred to destroy aliens, then given a magnificent beard to contain such power, he actually was born in Seattle. As a child, he worshipped the scientific greats like Stephen Hawking (the wheelchair guy) and Einstein. He loved physics, so he went on to MIT and graduated, becoming a liscenced Theoretical Physicist. For those that don't know, Theoretical Physicists study physics that may or may-not exist. And apparently study in the use of highly dangerous military-grade equipment, too. Also, it's a good bet they study the use of crowbars to solve every problem known to man.
Theoretical Physics 101
Later, while working for Black Mesa, a secret and self-contained government facility, he was involved in an incident that would change the face of humanity one day. Not the casserole incident, no. A failed experiment caused a rip in time-space, opening a vortex to a horrible dimension full of disgusting alien life-forms bent on taking over the Earth. With trusty crowbar in hand, Gordon Freeman took on an entire alien army, as well as the US Army, and eventually destroyed Rosie O'Donnel and freed the entire alien race under her control.
YOUR SHOW SUCKS, ROSIE!
After dissapearing for 20-odd years, Gordon awakens on a train headed for City 17, a city ruled by a man named Dr. Breen and controlled by the Combine, an evil alien race determined to make the world as Orwellian as possible. Donning the HEV Suit Mark V, and with crowbar in hand, he once again takes on an entire army. This time, he gets help from the rebels, who are all out to rescue the earth...and of course bone Eli Vance's daughter, Alyx. Gordon makes his way through the City, it's sewers, the outer water-ways, across wilderness, and so-on and so-forth. He manages to somehow take down Dr. Breen, but in this action, causes a dangerous explosion that levels the entire city. By accident, of course.
With this done, it was time to shut down the Combine's portal to earth. With some help from Dr. Asswipe...Dr. Magnussen, they managed to do so. At the same time, they also managed to launch a headcrab and an innocent garden gnome into space, another leap for mankind. Last he was seen, Gordon was off to explore the ruined wreckage of the Borealis, a ship in the arctic tundra that may hold the key to stopping the Combine for good.
First off, headcrabs fucking LOVE Gordon Freeman. We're pretty sure about that. We're not sure if it's his beard or those glasses, but headcrabs are drawn to him like fat kids to twinkies. Like Ashton Kutcher to bad movie scripts. While weak, headcrabs tend to take over the bodies of normal people, dress them in white shirts and jeans, then attack Gordon with no respect for his personal space. That's when he breaks out the crowbar and goes Theoretical Physicist on their asses.
Also, they have giant vaginas in their chests. Just lettin' you know.
Being immune to radioactive materials and pretty-tough against small arms, the best way Gordon has found to take them out is with a rocket launcher or his crowbar. It's assumed by many that the zombies, and by association of mind-control, the headcrabs, just want to hug Gordon. For some reason yet unknown, the headcrabs obviously love Gordon to death. Get it? See what we did there? TO DEATH?