this guy is so stupid this is the real story eh ehm
you start off in black mesa a testing place and you are in a train first and it takes up to 5~10 minuts for the train to make its stop then theres a police officer named barney he will open the train door for you and he will also open the door to black mesa and then you get in get your half life suit witch is pritty awesome then you have to do a test for black mesa some crystals from a alien planet called ZEN you put it in the chamber then alot of stuff goes rong aliens start attacking the earth and its up to you to stop the aliens from destroying the hole world now your first weapon will be a crowbar then you get a pistol then a shotgun some where around the story you get a cross bow MP5 rocket launcher then some lil alien things to throw at ppl and they start attacking every thing even you and theres gernades manual gernads some things you put on the wall and wen someone passes it they will blow up like hell and theres some bosses the game was created by VALVE they created portal HL2 team fortresses 2 counter strike SOURCE and yata blahblah so at some parts of the game you will see a hold man named GMAN hes kinda the enemy hes just doing crap while you are trying to save the world he is a bitch wen you really need him and all bec hes like some super dude and you have to fight the army they wer sent by the presedent to kill every one that was incolved with the project and at the end you will pick to help the wolrd once again or DIE! your get these opisons from you guessed who the bitch gman sorry if i spelled alot rong )= P.S. yuo can play multi player and theres alot of mods for the game