This is just more Half-life with more added to it. There are new weapons and new enemies and honestly I wasn't really enjoying it all that much. I like the Sniper Rifle and that is about it. There are moments that I liked namely the final boss that was more fun then the nelieth, but just like with the base game I just found it to be a frusturating time to complete. If you like the Original Half-life you are gonna like Opposing Force, but I didn't enjoy this game all too much.