HalfLife2, real innovative gameplay? No. Innovative presentation, but not gameplay. HalfLife 2 basic gameplay is no different than the original Doom. You run around and shoot stuff. In Doom you shot a barrel and it blew enemies. In HL2 you shoot a steel beam and it swings down and kills enemies. In Doom, you had a rocket launcher and picked up ammo and shot enemies. In HL2 you have a gravity gun that picks up objects in the map(ammo)and hurls it toward enemies. Its really the same thing, its just the Valve does it in a hell of a lot more cool way.