-Physics system, Everything is the levels will be interactive and will act like it's supposed to, even the fire will slowly spread around from place to place.
-Unscpripted AI, Your Enemies and Allies Will think for themselves and not choose from a list of actions like in
Half-Life 1 so you will have to think to survive in
Half-Life 2.
-More Guns, There will be about 22 weapons in Half-Life 2 Some Will return from Half-Life 1 such as the Crowbar and Crossbow, and some will be brand new.
-Drivable Vehicles, This time Vehicles wont be on a track, you can go where ever with them, some will even have guns you can control from the driver seat.
-Gordon Freeman!, He will be back and you will play as him again, he still wont talk thoughout the entire game.
-An Xbox port is in the works but we dont know anything else about it.
-Valve is Porting is Counter Strike and most likely the other mods they have made and Half-Life 1 as well over to the source engine.
-Many More things I have forgotton to add.
